Can Mavic Crossride's support 200 pounds safely?- Mtbr.com
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  1. #1
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    Can Mavic Crossride's support 200 pounds safely?

    I am concerned about strength of my current wheel set, which is a set of 2008 Mavic Crossride wheels. Each of these wheels are laced to a heavy rim (that has a large cross section) with 24 straight bladed stainless steel spokes. That means 12 drive side spokes in the rear wheel are carrying the majority of my 200 pound weight. My old wheel set had Shimano M756 hubs and Mavic 223 rims laced together with 32 DT Swiss Champion spokes in each wheel. I temporarily retired these wheels because the rear hub’s drive side cone and lock nut constantly worked its way loose and last summer finally pitted the free-hub cup. Replacing the cone, free-hub, the ball bearings and axle for $50.00 is not the issues that is preventing me from using these wheels--it is the narrow rims and the hassle of constantly retightening the cone and lock-nut on the rear M756 hub. Up until this year I have been riding on 26 x 2.0 tires, which fit in the 223 rims, however this year I bought 26 x 2.2 tires and really like the extra cushion and traction they provide over the 2.0 tires. 2.2 tires are too wide for the 223 rims so that is why I am riding on my Crossride wheels because the rims are wide enough to accommodate 2.3 wide tires. How much stronger are the 223 wheels with 32 spokes (16 effective spokes supporting the rear dished wheel) than the Crossrides with 24 spokes in each wheel?

  2. #2
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    Quote Originally Posted by bwalton
    That means 12 drive side spokes in the rear wheel are carrying the majority of my 200 pound weight.
    It's a lot worse than that. Your weight is standing on about three to four spokes. The less spokes the wheel has, the less spokes are supporting the weight, the more each one is doing and the more the wheel goes out of true if one breaks.

    How much stronger are.......wheels with 32 spokes than the Crossrides with 24 spokes in each wheel?
    We have no way of measuring that but the answer has got to be "lots".

  3. #3
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    I rode a set for 3 years until the paws in the hub and the bearings gave out. The 1st year I was at 220 and the next two years around 200. I checked the rims peridically in a truing stand, but never once made an adjustment. Aside from dings, the rims are as true as the day I bought them.

    Good luck

  4. #4
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    I had Crossrides a few years back when I weighed 195. Never had any problems and only switched because I crashed and ended up putting my foot through the front wheel which tore 3 spokes out of the hub. Being that it was a proprietary spoke and hub, I just got different wheels since it didn't make financial sense to repair.

  5. #5
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    Mike T, I took some spoke tension measurements this morning while sitting on three different bikes to get a feel if the Mavic Crossride rear wheel (559 x 19C—unknown ERD) is strong enough and durable enough to support my weight. My wife measured the tension of the three bottom spokes using a Park Tool TM-1 while I was sitting on the bike holding myself up on a door jamb. I weigh about 205 pounds with clothes and was sitting in a more upright position than I normally do when riding.
    2009 Mavic Crossride rear wheel with (24) two-cross 2.2-1.3mm S.S. bladed spokes. Unknown if the spokes are at a uniform tension on each side of the rear wheel:
    Rider’s Weight (pounds) Drive-side (Kgf) Left side (Kgf)
    0 137 76
    205 95-BDC 51
    205 107 76
    205 107 76

    Conclusion: Two spokes support the riders weight whereby (one) drive-side spoke is carrying the majority of the weight.

    Conventional 622 x17 wheel with (32) three-cross 2.0 straight gauge S.S. Wheelsmith spokes laced to a Specialized CT/Alex ACE17 or ACE18 (with an ERD of 602mm+) double walled (boxed) rim, which I re-laced after the OEM spokes started to fatigue:
    Rider’s Weight (pounds) Drive-side (Kgf) Left side (Kgf)
    0 121 to 137 56 to 62
    205 107 BDC 56
    205 137 62
    205 137 68
    Conclusion: Two spokes support the riders weight whereby (one) drive-side spoke is carrying the majority of the weight.
    Conventional 700 (622 x 14 with an ERD of 598mm) OEM road wheel with (32) 2.0mm generic S.S. straight gauged spokes laced to an Alex R500 double walled semi-aero rims in a three-cross pattern. I replaced one drive side spoke with a 14 Ga. DT Swiss Champion because the OEM one fractured at the threads. I adjusted all the spokes to have uniform tension on each side of the wheel, trued it radially and laterally within 0.5mm, dished it and stress relieved the spokes after I replaced the broken spoke:
    Rider’s Weight (pounds) Drive-side (Kgf) Left side (Kgf)
    0 121 to 137 56 to 62
    205 107 BDC 56
    205 137 68
    205 137 62
    Conclusion: Two spokes support the riders weight whereby (one) drive-side spoke is carrying the majority of the weight.
    BWW Commuting wheels with an Alex DH19 doubled walled rear rim (622 x18 with an ERD of 599.7) laced to a Deore hub with (36) 2.0mm straight gauged S.S. spokes in a three-cross pattern. Needless to say these wheels are bullet proof but heavy. I re-trued the rear wheel last year but never checked the tension of the spokes, which from the readings below are way too high and may not be uniform:
    Rider’s Weight (pounds) Drive-side (Kgf) Left side (Kgf)
    0 156 95
    205 179 76 BDC
    205 179 85
    205 179 95
    Conclusion: One spoke is carrying the majority of the rider’s weight or more likely the deep sectioned DH19 rim deflects so little under my 205 pound load that the tension meter and or my wife could not read the difference in spoke tension. (36) Over-tensioned spokes and a deep sectioned rim, which bridges the rider’s weight across many spokes is what makes this wheel so strong.

    From these quick imprecise readings of the 6 bottom spokes in the four sets of wheels, the two spokes on the bottom of the Mavic Crossride rear wheel compresses just like the two other rear wheels with 32 spokes. The Mavic’s combination of a deep section rim and pre-tensioned bladed spokes with reduced mid-sections can stretch more than a standard round straight gauged 2.0mm spoke without taking a permanent set (i.e. the cold formed stainless steel wire’s load cycle stays within its elastic zone) keeps the wheel strong enough to carry my 205 pound weight. Without the additional spokes to collectively add to the Mavic’s overall pre-tensioned structure, I do not believe this wheel has a lot of extra capacity if I were to hit a large bump at a fast speed or land from a bunny hop. I will put my old rear Mavic 223 wheel with 32 spokes on mountain my bike tomorrow and measure the tension on the six bottom spokes and see how they compare with these results.

  6. #6
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    nice work.

    what stuck out to me is that, predictably, the Mavic wheel spokes lose more tension than the conventional wheel spokes.

    however, it's pretty hard to discern anything if you don't know that spoke tension is uniform (which means you also don't know the starting tension of at least two of the three spokes you're measuring). are your wife's measurements repeatable?

    tension going up in the last wheel makes zero sense (as in, it didn't happen that way) and tells you there's a problem with the methodology.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  7. #7
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    I measured the static tension of a few random spokes in each wheel before I sat on the bike and let my wife take over the measuring when I sat on the bike. The (36) spoked commuter rear wheel by the BWW is over tensioned because the DH19 rim is so strong that it has the extra capacity to support the extra tension of the spokes without yielding (i.e. buckling or turning into a taco). So I believe the spokes that my wife measured did compress either very little or by a good 30 Kgf, which means they are tensioned to approximately 200+ Kgf. I will back the tension off to about 130 Kgf on the drive side this weekend so the nipples do not pull out of the rim holes.

  8. #8
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    Great stuff. When you're done can you please sum up your findings. I'm sure at that point, our learned friend meltingfeather will have interesting comments.

  9. #9
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    it's odd that the second and third wheelsets have exactly the same numbers for every measurement.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  10. #10
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    I really appreciate your analysis, but I have to question your finding of 200+ Kgf. That's way above our readings, and way above anything that we ever strive for.

  11. #11
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    A couple of comments:
    You don't need the wheel to be true, nor evenly tensioned for your measurement to be meaningful. However, you do need to measure the before and after tension of these bottom few spokes.
    The total tension change should be a reasonable fraction of your weight.
    I hope you are doing this with tires mounted and inflated.

  12. #12
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    February 1, 2011
    Listed below are the results of the second tension measurements that my wife and I took this morning of the 5 bottom spokes in five separate rear wheels. The methodology we followed for the tabulated measurements below is a lot more precise than the ones I listed yesterday in this post, which need to be discarded. First off, my wife measured the same five spokes using a Park Tool TM-1 spoke tension meter with and without my 205 pound body sitting on the bike seat in a riding position. The TM-1 was lubed, position as close to the center of each spoke as possible and the instrument’s spring calibrated push rod was slowly released against the spoke to get the most accurate measurement possible. Again the purpose of this exercise is to compare the strength and durability of a 2009 Mavic Crossride (559 x 19) two-cross rear wheel laced with (24) 2.2-1.4 S.S. bladed spokes in a 2X pattern with several conventional rear wheels with (32) or (36) 14 Ga. (2.0mm) spokes laced in a 3X pattern.
    The spokes are labeled 1 through 5 and are orientated with respect to a person viewing the rear wheel from the left side of the bike (i.e. the non-drive side).
    Spoke No. 1 a drive-side spoke positioned two rim holes in front of spoke No. 3.
    Spoke No. 2 is a left flange spoke positioned one rim hole in front of spoke No. 3
    Spoke No. 3 is a drive-side spoke at bottom dead center (BDC).
    Spoke No. 4 is a left flange spoke positioned one rim hole behind spoke No. 3
    Spoke No. 5 is a drive-side spoke positioned two rim holes behind spoke No. 3

    I. 622 x 18 Alex DH19 rim laced to a Shimano Deore non-disc hub with (36) 2.0mm generic straight gauged spokes in a 3X pattern. This wheel was built be the BWW a few years ago.
    Weight (lbs) Spoke 1 (Kgf) Spoke 2 (Kgf) Spoke 3 (Kgf) Spoke 4 (Kgf) Spoke 5 (Kgf)
    Bike >179 85 156 95 179
    205 168 76 121 76 179
    Difference unknown 12% 29% 25% 0

    II. 622 x 17 Specialized CT/Alex Ace17 or Ace18 rim laced to a Shimano Alivio disc hub with (32) 2.0mm S.S. straight gauged Wheelsmith spokes in a 3 X pattern. I re-laced this OEM wheel last year after three OEM non-drive side spokes fatigued/fractured at the elbow.

    Weight (lbs) Spoke 1 (Kgf) Spoke 2 (Kgf) Spoke 3 (Kgf) Spoke 4 (Kgf) Spoke 5 (Kgf)

    Bike 137 65 107 65 101

    205 137 56 85 51 95

    Difference 0 16% 26% 27% 6%

    III. 622 x 14 Alex R500 rim laced to a Joy-Tech or Formula hub with (32) 2.0mm generic straight gauged S.S. spokes in a 3 X pattern. I replaced one drive-side spoke last year that had a stress fracture at the top end of the thread.
    Weight (lbs) Spoke 1 (Kgf) Spoke 2 (Kgf) Spoke 3 (Kgf) Spoke 4 (Kgf) Spoke 5 (Kgf)
    Bike 137 <51 137 56 137
    205 121 <51 107 <<51 121
    Difference 13% unknown 28% unknown 13%

    IV. 559 x 17 Mavic 223 rim laced to a Shimano RH-M756 XT disc hub with (32) 2.0mm DT Swiss Champion straight gauged S.S. spokes in a 3 X pattern. This wheel was built two years ago by the BWW.
    Weight (lbs) Spoke 1 (Kgf) Spoke 2 (Kgf) Spoke 3 (Kgf) Spoke 4 (Kgf) Spoke 5 (Kgf)
    Bike 156 51 156 90 125
    205 137 <51 137 76 121
    Difference 14% unknown 14% 18% 3%

    V. 559 x 19 2009 Mavic Crossride (19.5 x 24.8 rim) with a Mavic ISO disc hub and (24) straight-pull bladed 2.2-1.4mm S.S. spokes laced in a 2 X pattern. This rear wheel has maybe 200 miles of wear on it.
    Weight (lbs) Spoke 1 (Kgf) Spoke 2 (Kgf) Spoke 3 (Kgf) Spoke 4 (Kgf) Spoke 5 (Kgf)
    Bike 131 55 125 67 121
    205 131 54 107 54 118
    Difference 0 2% 17% 24% 3%

    Notes;
    1. Any measurements that are preceded with a greater than or less than sign are off the Park Tool conversion chart for the TM-1.
    2. Difference is simply dividing the smaller number into the larger number and recording the numbers that follow the decimal as a percent. For example 100/80=1.25 or 25% change. This simplified calculation of percent change is not to be mistaken for percent difference. The percent change is used only as a rough indicator of the change in tension for each spoke.
    Unexpected results and questions:
    It is interesting that spoke number 4 in the wheels listed in I, II, IV and V compressed more than the spoke number 3, which is located at the bottom dead center (BDC) of all the wheels. Somehow these non-drive side spokes are carrying over 35% of the rider’s weight (or in my case over 72+/- pounds). So no wonder left spokes fail so often. I was under the impression that drive side spokes carried the majority of the rider’s weight because they need to be tensioned at twice the force as a left side spokes to center or dish the rim about center of the axle. Well these test results dispels this myth except for the Alex R500 road wheel, which must be dish more than the other wheels in this test.
    The next surprise is that the shallow 18mm tall by 23mm wide double walled Mavic 223 rim (an ERD of 538.5) laced with (32) 14 Ga. DT Swiss spokes deflected less than the three deeper rims under my 205 pound weight. The Alex DH19 (19mm deep x 24.6 with an ERD of 599.7mm), the Alex R500 (approximately 21 mm tall with and ERD of 598mm) and the Crossride rim (19.5mm tall x 24.8mm wide) all have slightly deeper sections than the Mavic 223 rim and therefore should be more rigid when loaded like a beam across the supporting spokes. The Crossride rim has the longest span between its spokes but did not deflect as much as the deepest rim out of the bunch—the Alex R500. The shallowest rim, the Specialized/Alex CT or Ace17, has the most rectangular section out of the five rims but also deflected the most out of the bunch. So how does a consumer pick a rim if section depth does not equate to beam or bridge strength?
    Lastly, is a strong wheel a combination of many over tensioned thin spokes laced to a shallow heavy rim, which loads up more than three spokes at a time? Or a wheel with a deep rigid rim supported by many over tensioned thick spokes? These five rear wheels did not answer this question. According to the book, The Bicycle Wheel by Jobst Bradt, (36) or “many” thin or swaged spokes tensioned to about 10% of the rims yield and laced to a deep rigid boxed doubled walled rim in a 3 X pattern makes a strong wheel.
    Summary of results translated into pounds support by each spoke:
    The Mavic Crossride is the weakest wheel out of the five rear wheels because my 205 pound weight is carried by two spokes somewhat equally or 102 ½ pounds per spoke.
    The Alex DH19 rear wheel in test sample I, distributes my 205 pounds across four spokes where the majority of the load is carried by the two bottom spokes or about 70 pounds/spoke. And Spokes 1 and 2 carry about 30 pounds each.
    The Alex R500 road wheel carries my body weight on the three drive-side spokes only in the following proportion: Spoke 1=58 ½ lbs, BDC Spoke 3=88 lbs and Spoke 5 58 ½ pounds.
    The Alex Ace17 wheel spreads its load across the three bottom spokes: Spoke 2=53 lbs, BDC Spoke 3=74 lbs and Spoke 4=78 lbs.
    The strongest rear wheel out of the bunch is the Mavic 223’s that predominately distribute my weight over three spokes somewhat evenly: Spoke 1=66 lbs, BDC Spoke 3=66 lbs and Spoke 4=73 lbs.

    Possible Errors:
    1. The TM-1 is two years old and may be out of calibration.
    2. The precision and accuracy of the TM-1 as well as its scale limits skewed the data. However; as an indicator instrument the TM-1 is more than adequate to measure general trends and relative tension differences between spokes.
    3. TM-1 operator error.
    4. Uneven left side and ride side spoke tension in the five test wheels.
    5. Taking one measurement of each spoke. A minimum of three measurements of each spoke should have been taken with two closely matching results to be statistically significant.
    6. More rear test wheels with deep sectioned rims and swaged spokes would have helped to prove Jobst Bradt’s theory that strong wheels are formed from these components.
    7. Rounding errors when calculating percent change and weight in pounds per spoke.

  13. #13
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    Without getting into the numbers, I rode the crap out of a set of Mavic Crossroc wheels (24 spokes, 2X, UST rim) and the rim and spokes were bomber. Can't say as much for the rear hub, but the spokes and rims did just fine.

    For the record I weighed between 205lbs and 225lbs during the years I rode them.

  14. #14
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    I have really enjoyed reading your findings, from a comparative analysis perspective. I can't comment on the other wheels, but regarding the DH19 36 hole wheel set, the referenced spoke tension measurements still seem extremely high. I may be a little confused though, are you converting Kgf to pounds of force, by any chance? That would produce higher #'s, but then your referenced tension readings (converted back to Kgf) would mean that the spoke tension would seem a little low.

    If the tension readings haven't been converted, that would mean that somehow spoke tensions have increased over time. Most rims/wheels aren't too happy past 130-140 Kgf, meaning calculable variances in spoke tension start creating lateral deviation when the wheel is stressed. IMO, most wheel builders are probably happy with consistent tension readings that are below 130, (or even much less).

    I don't use the Park tensiometer, so my practical knowledge with its usage is nil.

  15. #15
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    I may have misunderstood your earlier post, were you trying to calculate the rider weight that each spoke supported through some method of spoke tension % variance?

  16. #16
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    Quote Originally Posted by bwalton
    It is interesting that spoke number 4 in the wheels listed in I, II, IV and V compressed more than the spoke number 3, which is located at the bottom dead center (BDC) of all the wheels.
    This is wrong. Spoke 3 had the largest absolute change, as expected. The fractional change doesn't mean anything. Compression is proportionately related to change in lbs.

    Your results fail a basic sanity check, as I pointed out in a previous post: The sum of the tension changes has to be a reasonable fraction of the applied load.

    Looking at two examples:
    Crossride:
    unloaded 131 055 125 067 121
    loaded 131 054 107 054 118
    difference 0 1 18 13 3
    sum: 35

    DH19:
    loaded >179 085 156 095 179
    loaded 168 076 121 076 179
    difference>11 9 35 19 0
    sum >74

    So where did this extra weight go?

    The tension change distribution is peaked near the bottom spoke and tapers off as you go further (See the Bicycle Wheel for the more exact distribution). The sum of this lump is approximately the load applied. Any measurement that doesn't follow this pattern is suspect in both the individual measurement error as well as overall scale. This pattern doesn't depend on the initial tension of the spokes because that is only a preload and the elasticity of the spokes and rim determine the tension changes.

    You also didn't mention what tires you had mounted on the rims.

    I would fix your measurement technique before drawing conclusions about rims.

  17. #17
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    very nice work, mr. walton!
    Quote Originally Posted by bwalton
    Unexpected results and questions:
    It is interesting that spoke number 4 in the wheels listed in I, II, IV and V compressed more than the spoke number 3, which is located at the bottom dead center (BDC) of all the wheels.
    beanbag is right, it's the absolute difference that matters, not the percent change.
    Quote Originally Posted by bwalton
    So how does a consumer pick a rim if section depth does not equate to beam or bridge strength?
    due to the possible sources of error and basic inadequacies in the method that you point out as well as some suspicious results, I'd hold off on drawing conclusions from this work and applying them broadly.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  18. #18
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    Walton,

    I mentioned earlier, I do enjoy this type of information. There's so much 'heresay' readily available via a quick Net search, but IMO too little measured/quantified info.

    I'm sure you've already checked this out, but in the slim chance that you haven't, I'm sure you'll enjoy reading:

    http://www.sheldonbrown.com/rinard/wheel/index.htm

  19. #19
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    I appreciate the constructive feedback that I am getting so far—keep them coming. Here are some of the assumptions I brought into the exercise:
    1. A bicycle wheel is a pre-stressed structure, which is made up of a rim and thin tensioned wires anchored into a hub. The spokes directly under the rider’s weight (or some portion thereof) bear the majority of the load (i.e. the loaded spokes act like a columns). If the thin wires/spokes were not pre-tensioned then they would buckle under the rider’s weight and the wheel would collapse. 2.0mm diameter or 14 gauged wire spokes that range in lengths of 230mm to 280mm are way too slender to support any weight by themselves if loaded like a column. But a typical bicycle with 32 or 36 spokes is capable of supporting up to 400 Kg or 880 pounds when loaded radially. Also no more than 4 spokes support the riders weight (at the bottom of the wheel above the contact patch) and road dynamic loads (e.g. from pot holes). The spoke tension in the remaining spokes does not deviate more than 5% for clincher tire inflation loads, braking loads or torsional loads from pedaling forces acting through the rear hub/cassette. All of these theories are spelled out in Jobst Bradt’s book The Bicycle Wheel. That is why I only measure the tension of the five spokes in the bottom of the wheel and discarded tension changes less than 10%.
    2. I should have listed tires and tire inflation as other possible errors that could affect the tension of the test spokes. Each wheel had a different type of tire installed on it when my wife took the measurements. All of the 700 wheel tires were inflated to 80 psi +/- 10 psi and the two 26er wheel tires were inflated to 50 psi +/- 5 psi.
    3. Again based on Jobst Bradts findings, that the wheel stands on the bottom spokes, I portioned my 205 pounds over the few spokes that read more than 10% change in there tension. For example, if four spokes in the bottom of the wheel lost 25% of their tension when I sat on the bike then I divided my 205 pounds by 4 and recorded the resultant as 51 ¼ pounds per spoke. Again this probably is not the correct way to convert tension differences into pounds of weight carried per spoke but it gives me and the reader of this post a rough order of magnitude or feel of what portion of the rider’s weight each spoke must support. Note; that the rear wheels in this exercise did not see my full 205 pounds because my upper torso was bent forward with my hands on the handle bars in a riding position.
    4. Here is a list of the unsupported rim distances between each spoke or a simple rim span of the wheels used in this exercise:
    622 x19 Alex DH19 (ERD 599.7mm) with 36 spokes: span=52.337mm or 2.0625”
    622 x17 Alex ACE17 (ERD 603mm+/-) with 32 spokes: span=59.1994mm or 2.3125”
    622 x 14 Alex R500 (ERD 598mm) with 32 spokes: span=58.7085mm or 2.3125”
    559 x 17 Mavic 223 (ERD 538.5mm) with 32 spokes: span=52.867mm or 2.0625”
    559 x 19 Mavic Crossride (ERD 535.5mm +/-) with24 spokes: span=70.0968mm or 2.75”

    According to the tension reading taken yesterday, the Crossride rim with the longest span between spokes distributed my weight across only two spokes whereas all of the other four wheels with shorter rim spans distributed my weight across 3 or 4 bottom spokes. This conclusion is not earth-shattering but a deep sectioned rim that has a large bending stress capacity can span over larger distances than a shallow rim and most likely can be built with few spokes. The durability of a wheel with fewer spokes would driven by the fatigue cycle of the spokes and the rim and if the spokes are stress relieved by the builder because only one or two spokes will carry the riders weight and road shocks in the load effective zone at the bottom of the wheel.


    It seems like a strong rear wheel is built with a medium sectioned rim and lots of thin or swaged spokes. The rim would deflect over a long distance and transmit the rider’s weight into many spokes. Of course the rim and spokes would need to be build from materials that have a long fatigue cycle (in the millions) and built properly so that its spokes or rims are not stressed to the materials yield point.
    Last edited by bwalton; 02-03-2011 at 05:07 PM.

  20. #20
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    Without getting into the good reading above:

    Yes, Mavic Crossride wheels can support 200 pounds safely. So can the CrossMax USTs which reportedly were weaker than the Crossrides.

    I've ridden both, and I currently have Crossmax USTs on a bike.

  21. #21
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    I have a suggestion: measure by pitch. If you have a smartphone, I heard there are apps that do that. The procedure would go like so:

    For each wheel, measure the tension and pitch of a few spokes. Hold one finger at the crossing point and pluck in the middle with the other. Use the formula Tension = const * freq^2, and do a fit to find out what this constant is (which is wheel and spoke dependent). You might need separate constants for drive vs non drive side if the spokes cross at different points. This should also give you an idea how accurate your tensiometer is.

    Next, use a bathroom scale to find out how much weight you actually put on the back wheel.

    Once you have that, now do your spoke test again, using pitch only as the measurement. Make sure the tension changes actually sum up correctly this time.

  22. #22
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    Here is an article http://www.sheldonbrown.com/rinard/wheel/grignon.htm that measures radial stiffness of two conventional road bike wheels and compares them against several aero type wheels with deep sectioned rims, which are laced to their hubs with 18 or fewer spokes. I stumbled across this article at the end of the lateral stiffness article that CFoster recommended.
    1. Mavic Cosmic Expert with (18) aluminum straight pull 2.75-1.5mm bladed spokes laced to a 30mm deep rim has a radial stiffness of 13,500 lbs/in.
    2. Campagnolo wheel with (32) swaged 2.0-1.8mm convention spokes laced to a 12mm boxed rim has a radial stiffness of 13,500 lbs/in.
    3. A conventional Mavic wheel with (36) 2.0 straight gauged spokes laced to a 12mm boxed rim has a radial stiffness of 20,200 lbs/in. This 36 spoked wheel with a shallow boxed or double walled rim is 50% stiffer than the wheels listed above in 1 and 2.
    This experiment does not qualify or quantify wheel durability nor does outline how the radial stiffness was measured and derived.
    I will re-measure the Alex DM19 rear wheel this weekend after I balance it’s spoke tension and bring the drive side spoke tension down to 125 Kgf max.. Hopefully this non-eyeleted rim is not cracked around any of its spoke holes.

  23. #23
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    240lb's when I had mine, they lasted up surprisingly well worked fine with 2.3" tires maybe even 2.4" and great hubs to be fair.

    I did destroy a newly fitted new rim from the front in 1 very rocky peaks descent but I was landing drops on rocks and had rim strikes so it's not surprising, but lasted ages for normal none insane forest useage.

    Really easy to replace a spoke to, which is handy cause if 1 snaps there unrideable, but you can easily fit in sub 10mins on the trail thanks to the straight pull, I used to tape 1 or 2 to my frame.

  24. #24
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    Back in 2005 I purchased a set of Mavic Crossroads, which came with UST rime strips. These wheels had 21+mm deep rims laced to Mavic hubs with (24) 2.0mm S.S. straight pull straight gauged spokes. These wheels lasted for 2 1/2 years before one of the eyelets loosened up and started to creak. I know that these types of Mavic wheels can last for two years without spoke failure assuming that the owner uses them for XC riding only. And they can support a 200 pound plus rider but how much extra reserve do 24 spoked wheels have? In the same light, what about road wheels with 20 spokes and fewer, can they safely carry a heavy rider on rough AC blazing down a hill at 25+ MPH? How in the world can a wheel with 24 spokes or less carry a heavy rider safely is a question that has been largely unanswered since I learned to build wheels a few years ago. The author of The Bicycle Wheel is quite adamant that (36) swaged spokes laced to a deep section 700 rim is the most durable and strongest wheel that can be built. Yet wheels with far fewer spokes servive—why?

  25. #25
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    Quote Originally Posted by bwalton
    The author of The Bicycle Wheel is quite adamant that (36) swaged spokes laced to a deep section 700 rim is the most durable and strongest wheel that can be built. Yet wheels with far fewer spokes servive—why?
    Because they are strong enough for the purpose at hand. Duh.

  26. #26
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    Alright let’s put some numbers on these results:
    Base line wheel strength, which equals the maximum weight a single wheel can support. According to Jobst Bradt’s book “The Bicycle Wheel” a typical road bike wheel (unknown if it is a front or a rear dished wheel with a deep or shallow depth boxed rim) with 36 spokes laced in a three-cross pattern can support 400 Kg or 880 pounds.
    If we ignore the collective spoke tension that contributes to the overall strength of the 2 or 3 or 4 spokes that carry the load at the bottom of each wheel and ignore the bending strength of the rims and simply base wheel strength off of the simple span between two adjacent spokes:
    I. 622 x 18 Alex DH19 with (36) spokes: Unsupported rim span of 2 1/16”--supports 882 pounds.
    II. 622 x 17 Alex CT or ACE17 with (32) spokes: Unsupported rim span of 2 5/16”--supports 776 pounds.
    III. 622 x 14 Alex R500 with (32) spokes: Unsupported rim span of 2 5/16”--supports 776 pounds.
    IV. 559 x17 Mavic 223 with (32) spokes: Rim span between spokes equals 2 1/16”--supports 882 pounds.
    V. 559 x 19 Mavic Crossride with (24) spokes: the rim span between spokes equals 2 ¾”-- supports 591 pounds.
    Wheel strength simply based off the number of spokes (e.g. 36 spokes is 12.5% stronger than 32 spokes, 36 spokes is 50% stronger than 24 spokes and 32 spokes is 33% stronger than 24 spokes):
    I. Alex DH19 with (36) spokes: 882 pounds.
    II. Alex CT/ACE17 with (32) spokes: 772 pounds.
    III. Alex R500 with (32) spokes: 772 pounds.
    IV. Mavic 223 with (32) spokes: 772 pounds.
    V. Mavic Crossride with (24) spokes: 441 pounds.

    Average capacity of both rim span and spoke count wheel strength results:
    I. Alex DH19=882 pounds.
    II. Alex CT/ACE17=774 pounds.
    III. Alex R500=774 pounds.
    IV. Mavic 223=827 pounds.
    V. Mavic Crossride=516 pounds.

    Evaluating wheel strength from these simplified percentages it is clear that the Mavic Crossride can support 2 ½ times my body weight, which is 205 pounds. However; when adding dynamic loads to the rider’s weight, the wheel’s 2 x safety factor is reduced down to close to zero.
    Obviously there are other factors that contribute to a wheel’s strength aside from spoke count and rim span. Jobst Bradt’s uses a 500N or 2,224 pound force in his wheel calculations, which accounts for all dynamic loads a typical wheel may encounter.

  27. #27
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    Aren't you also worried about your bars, seat rails, pedal spindles, and seatpost binder bolt?

  28. #28
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    Quote Originally Posted by bwalton
    Jobst Bradt’s uses a 500N or 2,224 pound force in his wheel calculations, which accounts for all dynamic loads a typical wheel may encounter.
    500N is 110 lbs

  29. #29
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    The measurements are interesting, I'm learning, even tho it is hard for me to imagine the spoke supporting the wheel in compression.

    That said, I owned some circa 2008 Cross Ride wheels. I weigh 185 w/o gear. They were the version with the V brake track. And they sucked.

    Flexy as hell. They picked their own lines. Small jumps were not an issue, just the wandering rim.

    And I think the reason for it is not the number of spokes, but the rim. A rim not optimized for stiffness, but optimized to use disc and rim brakes. IMHO, blame the wheel weakness on the rim not the spoke count. (I've been on 32 spoke noodles too)

    And when considering the weakness of 24 spokes, also consider the CrossMax SX. 24 spokes that get hucked into oblivion. No one complains about wheel flex nor weakness with those wheels. And they have ~500g rims, with rim material removed between spokes.

    Easton Havok is another example.

    Cross Lines have 28 spokes and are for hucking, DeeMax are 28 front 32 rear and are for hucking +. No one complains about wheel strength with these wheels. Think Mavic knows something?

    Conventional wisdom on these forums is that a wheel is as good as it's build. IMHO, it is a complete system, rim/spoke/hub/build for total strength.

    P

  30. #30
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    The radial strength of a wheel is approximately the force needed to slacken the bottom spokes. Usually lower spoke rims are built with higher spoke tensions to compensate for this. U can measure this by pitch only, and not even use a tensiometer. Pluck the bottom spoke and measure the pitch change when adding weight, or if you are musical, how many notes it changes by. That tells you the fractional change in tension, and you need that many times more force to slacken the spoke.

    Quit making up numbers.

  31. #31
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    I just found the technical documents for the 07, 09 and 11 Crossride wheel sets and the 2011 wheels can carry an 85 Kg or 187 lb rider and the 2009 wheels with the same rim depth and spoke count can carry a 100 Kg or 220 pound rider. The 2007 Crossride technical document did not specify the maximum rider's weight.

    Both of Mavic's 2011 Aksium and Ksyrium (622 x 15) road wheels with (20) bladed spokes in each wheel can support a 100 Kg or 220 pound rider.

  32. #32
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    The hub isn't standing on the bottom spokes, it's hanging from the top ones.
    When you put weight on the hub, tension increases in the top spokes which will try to pull the top part of the rim down.
    As a result of the top part of the rim going downwards, the rim will start to take on an oval shape, increasing the tension in all the spokes except a few at the bottom.
    In the bottom ones, tension decreases, indicating a lesser load.

    Quote Originally Posted by bwalton
    Conclusion: Two spokes support the riders weight whereby (one) drive-side spoke is carrying the majority of the weight.
    The right conclusion to draw is: All spokes except two support the riders weight.
    When it's 20 below freezing and the snow lays 10 inches deep, bicycle commuting kind of sucks.

  33. #33
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    Quote Originally Posted by ragnar.jensen
    The hub isn't standing on the bottom spokes, it's hanging from the top ones.
    OMG!! The resident engineers on this site will be along soon to give you an intro into basic pre-stressed structures science. While you're waiting, read Jobst Brandt's wheelbuilding book (another engineer) and get out the KY Jelly.

  34. #34
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    Wait for it.........

  35. #35
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    Quote Originally Posted by CFoster
    Wait for it.........
    I'm feelin' it comin'.

  36. #36
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    WOW!! All that time analyzing and typing? You could have ridden 20 miles. Cross Rides are tough wheels I rode them on a Jamis Dragon for two years. I used to weight 230. I'm down to 185 and riding CrossMax SLR's now. Mavic Wheels are bomb proof!!
    Don't worry bout it!!

  37. #37
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    2 spokes support the riders weight, while stationary I presume ??


    Errrr NO for starters you seem to think the spokes at the bottom hold you and get tighter WRONG, the spokes at the top hold you + bike in place, they support the weight not at the bottom.

    Yes the ones at the top support most of the weight as you move around the angle is more so the weight supported is lower, where as the lower spokes actually go slacker, but we really aren't talking much.

    I had Crossride 07's £106 for the set major bargain, didn't use the front for long as I went 29" on the front, used the front rim to rebuild the rear after I spanked it, but I spank all my rear wheels didn't do aswell as a Mavic 321 but not much worse considering it's weight.

  38. #38
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    Thinking out loud, but we dont just stand on spokes right? We hang on them too?

    Is this incorrect?

  39. #39
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    Yes the weight of a rider stands on the thin wire spokes at the bottom of the wheel. Think of a wagon wheel with thick rigid wooden spokes and a thick wooden wheel spanning between the spokes. The weight from the carriage is transmitted through the wheel's axle and down through the spoke or spokes directly underneath the axle at the bottom of the wheel. The wooden spokes act like small columns that are continuously loaded at the bottom of the wheel and unloaded as they roll/rotate away from the load zone. Since the wheel is not a solid disc, the rim of the wheel needs to be tall enough to support the carriages load between the spokes in the load zone--i.e. the rim acts like a beam between to columns. The bicycle wheel behaves just like a wagon wheel except the spokes are very thin (in order to save an enormous amount of weight). If the spokes in a bicycle wheel are not tensioned then the weight of the rider would buckle the spokes at the bottom of the wheel which in turn would taco the rim and the wheel would collapses. The wire spokes are strong enough to carry a rider's weight--they are just way too thin or slender to hold the weight up without buckling. That is why the spokes in a bicycle wheel are tensioned so they do not buckle under the loads of the rider and road. The basic bicycle wheel design is a series of trade-offs: keep the bicycle wheel light, inexpensive, quick and easy to assemble, strong enough to support the given design loads and of course marketable. The current trend in wheels (especially road wheels to decrease aerodynamic loads) is to decrease the spoke count while increasing the rim depth to compensate for the longer span between two spokes and the load zone at the bottom of the wheel. The reason I did this exercise in the first place is to figure out a way to put a quantitative value on how much weight a given wheel can support. At 200 plus pounds, I constantly break non-drive side spokes and my rear rims often go out of true. I plan to build a set of road wheels this month and maybe mountain bike wheels as well and wanted to get a feel for how spoke count and rim depth effect wheel strength an durability.

  40. #40
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    While the wagon wheel analogy is easy to comprehend as it has structure on both sides of the spoke, the challenge to understand for us non-engineering folk, is that a bike wheel spoke has structure at the base of only one side of the spoke and pulls only on the other side.

    Probably one of those counter intuitive engineering things.

    I have seen comments of big riders with 24 spoke Mavic ST wheels that do big drops and eject the heads of the spokes from the hub. The wheel remains round and true afterwards, but the rim clearly deformed on impact to eject the spoke head from the spoke seat in the hub. In this wheels case the spoke at the rim is firmly attached while the hub side is pull only. Regardless, this does appear that the spoke is not supporting the wheel if it is getting pushed up far enough to come out of the seat. But hey, I'm a newb to this, and from this example you can see how it is hard to understand a spoke working in compression.

    P
    Last edited by Mr.P; 02-06-2011 at 11:14 AM.

  41. #41
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    Quote Originally Posted by bwalton
    Yes the weight of a rider stands on the thin wire spokes at the bottom of the wheel.
    Nope, Look at a spoke in a bicycle whee (Not a Wagon Wheel). The Nipple floats when there is force applied at the bottom. Except for Mavic wheels where the spoke floats at the Hub. Either way you are hanging from the top spokes when sitting on your bike.

  42. #42
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    Quote Originally Posted by CarlosG
    Nope, Look at a spoke in a bicycle whee (Not a Wagon Wheel). The Nipple floats when there is force applied at the bottom........you are hanging from the top spokes when sitting on your bike.
    Bzzzzt. Thanks for playing. That would only be true if there was zero tension in the spokes.

  43. #43
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    All you have to do is look at how a spoke nipple sits in a wheel to see how it works. put away your tension meters. and gram scales and go ride your bike!!

  44. #44
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    Quote Originally Posted by Mike T.
    Bzzzzt. Thanks for playing. That would only be true if there was zero tension in the spokes.
    Given enough force there will be zero tension in the bottom spokes. Thats about the point you hear a loud ping and you wrap your spokes around your hub and scream.......... OH ****!!!!

  45. #45
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    Quote Originally Posted by bing!
    Thinking out loud, but we dont just stand on spokes right? We hang on them too?

    Is this incorrect?

    YEP completely, Anyone who is still banging on about the spokes at the bottom taking the weight is an IDIOT, spokes only work under tension ie hanging from, not under compression when they just bend.

  46. #46
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    Less blah blah, more trying....

    Pluck the top and bottom spokes with and without a load on the wheel and see which ones change in tension by more. There's too much wrongness in this thread.

  47. #47
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    Quote Originally Posted by beanbag
    Pluck the top and bottom spokes with and without a load on the wheel and see which ones change in tension by more. There's too much wrongness in this thread.

    They both sort of change by the same amount, the top ones increase in tension by the same amount of mm's stretch as the bottom ones decrease in tension by.

    Any more or less is your rim deforming as you put a load on it.

  48. #48
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    Quote Originally Posted by Turveyd
    They both sort of change by the same amount, the top ones increase in tension by the same amount of mm's stretch as the bottom ones decrease in tension by.

    Any more or less is your rim deforming as you put a load on it.
    Try it and report back

  49. #49
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    Quote Originally Posted by Turveyd
    Anyone who is still banging on about the spokes at the bottom taking the weight is an IDIOT, spokes only work under tension ie hanging from, not under compression when they just bend.
    And the earth is still flat in your world is it? You've just discredited the whole science of pre-stressed structures which engineers have thus been wrong about all these years. I'm sure they will sign you up for their next symposium where you can explain to them where they got it all wrong. Please read up on Brandt's book before you make yourself look any worse.

  50. #50
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    Do all the calculations and measuring you want.

    I have the cross rides, weigh 210 lbs and ride intermediate cross country. I bought the wheels as a cheap stand by as I make my custom wheels. I would not recommend these wheels for anyone over 200 lbs. The rear wheel creaks and cracks and goes out of alignment every other ride. This last ride one rear spoke was so lose I'm surprised it didn't puncture the inner tube, the nipple was completely driven into the rim to the point that it wasn't visible.

    Front wheel has been fine.

    If these make it another 3 months I'll be happy.

  51. #51
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    Let met attempt to further refine how all the tensioned spokes behave in a bicycle wheel. Jost Bradt (author of The Bicycle Wheel) ran three different FEM calculations of a bicycle wheel, which produced a model of all the spoke length differences for a given wheel load. Using a (36) spoked wheel model, the (3) spokes at the bottom of the wheel (above the contact patch) compressed by 0.1000+/- mm while the remaining (33) spokes arrayed around the wheel either compressed or elongated less than 5% (0.0010+/- mm) when ridden on by a typical sized rider. He also added a rim brake and torsional hub load from the cassette gears to the riders load and found that (33) spokes around the three bottom ones also changed less than 5% in their static length. Anyone can test this by plucking the spokes just above their nipples like a guitar string and hear the tone changes between them. You will find that only the bottom spokes sound different when someone sits on the bike because they are supporting the vast majority of the rider’s weight and compress/shrink in length like columns do. All I did for this exercise is to use a spoke tension meter to measure the changes in the bottom spokes instead of using tone or measuring spoke length differences, which I cannot do accurately with a tape measure. In summary, the (33) spokes arrayed around the (3) bottom spokes keep the bottom spokes tension under the riders weight and road impacts. If the spokes are under very little tension or if the rider’s weight combined with a road impact is great enough to deflect the rim in to de-tension the bottom spokes than the rim will taco.

  52. #52
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    Quote Originally Posted by Mike T.
    And the earth is still flat in your world is it? You've just discredited the whole science of pre-stressed structures which engineers have thus been wrong about all these years. I'm sure they will sign you up for their next symposium where you can explain to them where they got it all wrong. Please read up on Brandt's book before you make yourself look any worse.

    As it seems Brandts book would support spokes at the bottom ie going toward the floor support your weight, I think I'll give it a WIDE WIDE Berf thanks.

    Try this, take out 40% of your spoke and put the wheel missing spokes down, then put weight onto the bike / wheel and notice the wheel still works as a load carrier, know put the wheel the other way up and notice the big crash to the floor with spokes bending.

    Then you'll get the hint!!

    A little bit of mis information + IDIOT = DISASTER!!

  53. #53
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    Quote Originally Posted by Turveyd
    As it seems Brandts book would support spokes at the bottom ie going toward the floor support your weight, I think I'll give it a WIDE WIDE Berf thanks.
    Try this, take out 40% of your spoke and put the wheel missing spokes down, then put weight onto the bike / wheel and notice the wheel still works as a load carrier, know put the wheel the other way up and notice the big crash to the floor with spokes bending.
    Then you'll get the hint!!
    A little bit of mis information + IDIOT = DISASTER!!
    Dohhh you're RIGHT!! You just changed hundreds of years of science Turv. Our forum faker meltingfeather had best give you his engineering degree diploma. You're a frikkin' genius.

  54. #54
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    Quote Originally Posted by Mike T.
    Dohhh you're RIGHT!! You just changed hundreds of years of science Turv. Our forum faker meltingfeather had best give you his engineering degree diploma. You're a frikkin' genius.

    Haven't changed 100 years of science, I merely understand the science and don't believe the first piece of bad science I hear cause it's the first thing I heard and then have to aggressively defend this despite it having no logic behind it what so ever rather than admit your wrong.


    Take some spokes out of a wheel and see for yourself, open your mind!!

  55. #55
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    Quote Originally Posted by Turveyd
    Take some spokes out of a wheel and see for yourself, open your mind!!
    Take the pre-stressed steel out of a concrete beamed bridge, drive over it with a 50-ton truck and prove that that pre-stressed structure doesn't work too. Well, it's the same logic that you just came up with.

  56. #56
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    Quote Originally Posted by Mike T.
    Take the pre-stressed steel out of a concrete beamed bridge, drive over it with a 50-ton truck and prove that that pre-stressed structure doesn't work too. Well, it's the same logic that you just came up with.

    Your taking the science from 1 thing and applying it to something completely different as if it was the same, it isn't.

    You realise you can build a wheel with string literally, it'll work reasonibly well allowing for the reduced strength of string, string at the bottom you've got to agree has zero real strength at the bottom and hangs from the top quite nicely.

    It's interesting further back on the spoke tension measurements, but something is going wrong with the measurement method, nothing more.

    Go on your wheel builder, strip some spokes out and give it a try.

    Push to ends of a spoke together, they bend, pull the ends apart and it will take the strain.

  57. #57
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    Ohhh tension meter is giving a bogus reading cause the weight above is putting a curve into the spoke and the curve although not load bearing is creating resistance and screwing up the data.

    The top spokes are being pulled straighter and the meter would likely read them as less tension.

    There bogus readings and people reading to much into them.

  58. #58
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    Try the spoke plucking test. It's easier than taking out spokes. Or would you prefer a theoretical explanation of your wrongness?

  59. #59
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    Quote Originally Posted by Turveyd
    Your taking the science from 1 thing and applying it to something completely different as if it was the same, it isn't.

    You realise you can build a wheel with string literally, it'll work reasonibly well allowing for the reduced strength of string, string at the bottom you've got to agree has zero real strength at the bottom and hangs from the top quite nicely.

    It's interesting further back on the spoke tension measurements, but something is going wrong with the measurement method, nothing more.

    Go on your wheel builder, strip some spokes out and give it a try.

    Push to ends of a spoke together, they bend, pull the ends apart and it will take the strain.
    You're forgetting one basic thing Turv. A bike wheel is the best synergistic structure ever invented IMO. It's not a usable load-bearing bike wheel if you take out too many spokes. This is what you're not seeing. Let's use my made-up figures and you'll see where I am going. Let's say ALL the spokes have 400lbs of tension on them, pulling inwards. Sit on the bike with your 200lbs. Nipple heads push out from the rim at the bottom creating slack spokes? Not even close. Why not? Because if you now measured their tension, they would still have 200lbs on them, pulling the nipples against their seats. Hit a bump which creates a 300lb instant load. Same result and reason as above; different numbers. There's still 100lbs of tension left, still pulling those nipples against their seats. Hit a BIG bump causing 401lbs of force. Nipples come away from the rim? Yep they did for an instant while the bump was under the wheel. For that short period of time, a small few lower spokes were not supporting you as their tension was reduced to zero. If the nipple was welded to the rim, the spokes would have buckled.

    A bike wheel is a homogeneous unit, not a few spokes allowing a hub to dangle from a rim. I wish I had time to find meltingfeather's engineering explanation, or better still, that he would come along. It's ok by me if you can't understand all the above Turv but don't regress to name-calling as there are a few smart people around here, in the background, rolling their eyes and watching you make a fool of yourself. But maybe you are smart and you're just a Troll.

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    It's also inaccurate due to the other forces being exerted on the spokes which is changing the pitch / propertys of the spoke.

    The question is, not what does a meter / plucking read but where is the load being supported, I've highlighted how to test for this so go try it.

    IF I can find my old dead Crossride I'll strip out spokes and take photo's to prove it.

    Not that you've believe my photo's ofcourse.

  61. #61
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    Quote Originally Posted by Mike T.
    You're forgetting one basic thing Turv. A bike wheel is the best synergistic structure ever invented IMO. It's not a usable load-bearing bike wheel if you take out too many spokes. This is what you're not seeing. Let's use my made-up figures and you'll see where I am going. Let's say ALL the spokes have 400lbs of tension on them, pulling inwards. Sit on the bike with your 200lbs. Nipple heads push out from the rim at the bottom creating slack spokes? Not even close. Why not? Because if you now measured their tension, they would still have 200lbs on them, pulling the nipples against their seats. Hit a bump which creates a 300lb instant load. Same result and reason as above; different numbers. There's still 100lbs of tension left, still pulling those nipples against their seats. Hit a BIG bump causing 401lbs of force. Nipples come away from the rim? Yep they did for an instant while the bump was under the wheel. For that short period of time, a small few lower spokes were not supporting you as their tension was reduced to zero. If the nipple was welded to the rim, the spokes would have buckled.

    A bike wheel is a homogeneous unit, not a few spokes allowing a hub to dangle from a rim. I wish I had time to find meltingfeather's engineering explanation, or better still, that he would come along. It's ok by me if you can't understand all the above Turv but don't regress to name-calling as there are a few smart people around here, in the background, rolling their eyes and watching you make a fool of yourself. But maybe you are smart and you're just a Troll.

    So your going to invalidate my test, because without spokes it's no longer a wheel as such, you know what the results would be, your just unwilling to accept your wrong.

    I'm not a troll at all, I hate bad science there is to much of it around, this is bad science. ( your not mine )

    Look up those Disco wheels was it ?? going back 15year most likely, can't remember who made them, they worked off wire with plastic sheilds protecting them or something, how can wire support a load from compression rather than tension ?? answer it can't, just like spokes.

  62. #62
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    Quote Originally Posted by Turveyd
    2 spokes support the riders weight, while stationary I presume ??


    Errrr NO for starters you seem to think the spokes at the bottom hold you and get tighter WRONG, the spokes at the top hold you + bike in place, they support the weight not at the bottom.

    Yes the ones at the top support most of the weight as you move around the angle is more so the weight supported is lower, where as the lower spokes actually go slacker, but we really aren't talking much.
    This is wrong. The rider's weight is supported by the drop in tension of the lower spokes. The upper spokes do not change appreciably and do not support load.
    Quote Originally Posted by pvd
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    By the way I've had entire forums against me on topics such as this for months on end, I've then been proved right, don't think because loads of people disagree with me and are rolling there eyes at me that this makes them correct.

    And wheels although tricky to build well ( I build my own to very well thanks ), aren't exactly rocket science, not that rocket science is actually that tricky.

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    Quote Originally Posted by Turveyd
    As it seems Brandts book would support spokes at the bottom ie going toward the floor support your weight, I think I'll give it a WIDE WIDE Berf thanks.

    Try this, take out 40% of your spoke and put the wheel missing spokes down, then put weight onto the bike / wheel and notice the wheel still works as a load carrier, know put the wheel the other way up and notice the big crash to the floor with spokes bending.

    Then you'll get the hint!!

    A little bit of mis information + IDIOT = DISASTER!!
    it is a tricky concept, i'll grant that, but you're wrong here.
    your 'experiment' wouldn't prove anything because as soon as you cut 40% of the spokes out, you change the fundamental nature of the structure.
    so you mean to tell me that all capable analytical thinkers who have looked at the structural performance of bike wheels have gotten it wrong and you have figured it out? good luck with that.
    Quote Originally Posted by pvd
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    Quote Originally Posted by meltingfeather
    This is wrong. The rider's weight is supported by the drop in tension of the lower spokes. The upper spokes do not change appreciably and do not support load.

    How can lower tension, support weight ?? your contradicting yourself here and can't even see it.

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    Quote Originally Posted by Turveyd
    How can lower tension, support weight ?? your contradicting yourself here and can't even see it.
    it's you who can't see it.
    if we're playing tug of war and pulling against eachother in balanced equilibrium, then all of a sudden i pull less, you move backward, but i didn't push you, i just pulled less. same thing with a spoke.
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  67. #67
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    Quote Originally Posted by meltingfeather
    it is a tricky concept, i'll grant that, but you're wrong here.
    your 'experiment' wouldn't prove anything because as soon as you cut 40% of the spokes out, you change the fundamental nature of the structure.
    so you mean to tell me that all capable analytical thinkers who have looked at the structural performance of bike wheels have gotten it wrong and you have figured it out? good luck with that.

    Even consider these options :-

    1. you've not listened to a credible 1 ??
    2. You've not understood what a credible 1 is going on about and thus wrongly interpreted it.

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    Quote Originally Posted by Turveyd
    Even consider these options :-

    1. you've not listened to a credible 1 ??
    2. You've not understood what a credible 1 is going on about and thus wrongly interpreted it.
    I've spent a good bit of my life studying structures and tackling the challenging and counter-intuitive nature of pre-stressed structures in particular.
    I think it is you who does not understand, but if you can't point out a fatal flaw in any/all of the quantitative analysis done on bike wheels that shows that the wheel is undoubtedly supported by the drop in tension of the spokes at the bottom, I'm all ears.
    Quote Originally Posted by pvd
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    Quote Originally Posted by meltingfeather
    it's you who can't see it.
    if we're playing tug of war and pulling against eachother in balanced equilibrium, then all of a sudden i pull less, you move backward, but i didn't push you, i just pulled less. same thing with a spoke.

    Nope I believe it's the other way around, but I have a open enough mind to accept the possibility of being wrong and therefore keep trying please.

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    Quote Originally Posted by Turveyd
    By the way I've had entire forums against me on topics such as this for months on end, I've then been proved right, don't think because loads of people disagree with me and are rolling there eyes at me that this makes them correct.
    Prove yourself right then. Point out the flaw in logic, interpretation, or methodology in the this paper.
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    Quote Originally Posted by meltingfeather
    I've spent a good bit of my life studying structures and tackling the challenging and counter-intuitive nature of pre-stressed structures in particular.
    I think it is you who does not understand, but if you can't point out a fatal flaw in any/all of the quantitative analysis done on bike wheels that shows that the wheel is undoubtedly supported by the drop in tension of the spokes at the bottom, I'm all ears.
    WHAT, so you where supporting the claims of increased lower spoke tension, but know claim, lower tension at the bottom, which is ofcourse correct and fine come on explain how a spoke with lower tension that none stressed can support weight.

    Come on go full on science on me, I can handle it!!

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    Dont know if this has any bearing on what you all are talking about, but

    http://www.duke.edu/~hpgavin/papers/...heel-Paper.pdf

    On another note, I have always been told that the bottom spoke also supports the riders weight like a pillar, BUT since the wheel is a rotating force, then as the wheel rotates between the spokes, it would seem logical to me that at some point in time, some of that load of the rotating wheel also has to be supported by other spokes. The problem I see is that the load changes so fast around the rim, that it would seem to be impossible to measure. I guess it really doesnt matter since it seems that all the spokes have load all the time. I dont know?

    On another note, the pillar theory seems logical. Here is my take on it. Since most spokes break due to being under tensioned, The pillar theory would hold true. The reason being as the spoke is stressed vertically on end like a pillar, the spoke would flex, the resulting "snap" back (weight is unloaded) is what usually breaks the spoke(in my opinion). On the other hand, you could take a spoke, suspend it from the ceiling or whatever, and probably hang 500+ lbs on it, and it wont break, BUT if you were to lift that weight and release it quickly( an under tensioned spoke on the bottom of the wheel), most likely the spoke will break. (Just my theory)

    In reality, Im not looking to reinvent the wheel, so it doesnt really matter to me. I just tension the spokes, and they work. As to the OP, i say ride em, if they work, great, if they dont then get a different wheel combo.
    Last edited by nov0798; 02-07-2011 at 01:51 PM.

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    Nice science in the second paper and rubbish science in the first paper!!

    A wagon wheel spoke is strong and won't compress like a thin metal spoke which will deform.

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    put a spoke on your desk, I've got 1 in my hand, give it any side loading and you can bend the spoke relativity easily so both ends meet if you wish.

    As you've already stated, if you load the wheel enough vie the hub, the spokes nipple will lose contact with the rim, how can this spoke be supporting the rim as it's not even contacting it.

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    The concept that is really hard to visulize here is the height-to-slenderness ratio of a load bearing column or spoke in a bicycle wheel. I think everyone agrees that if we take a 2.0mm diameter steel spoke and cut it down to 1mm in length and somehow lock the bottom cut end on a thick "rigid flat steel plate and mount a 1/4" x 4" diameter plate on the top cut end of the spoke (directly over its center) and then place a very stable 200 pound weight over the center of the 4” round plate that the 2mm x 1mm steel wire will have no trouble holding up the 200 pound weight. The steel wire with a 36,000 psi minimum yield is far from flattening out like a pancake for a very small 200 pound load. Now lets increase the length of the 2.0mm wire to 4mm and load it up in the same manner with a 200 pound weight—the wire is now too slender and will buckle under the weight. Note; that the wire’s 36K material and 2mm cross section have not change and are more than capable of supporting the 200 pounds, only the length of the wire column has change, which caused it to buckle under the load. Pre-tensioning this 2.0mm x 4.mm long spoke in this jig, to say 100 Kgf, would allow it to carry the 200 pound weight without buckling. I know this may not be the best example because it is hard to separate the additive effect of the weight minus the tension, but that is precisely how a bicycle spoke at the bottom of the wheel is continuously loaded and unloaded. Structural Engineer’s factor in this slenderness ratio when they design a column otherwise the column could buckle and the building could potentially collapse. If a thin wire is hard to visualize than picture a 2 x 4 wood stud as the test column in different lengths with a 200 pound weight on top.

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    It doesnt loose contact with the rim per se. If you have 500 lbs of force on the spoke in tension, and you place 300 lbs of vertical load on that spoke, you still have 200 lbs of tension on the spoke that is holding the nipple against the rim. Until you exceed the stressed value, then all is good! If you exceed the value, then that is where you get your broken spokes, when the spoke does loose contact with the wheel the resulting snap back to tension then exceeds the max value of the spoke and breaks it. Again my opinion.

  77. #77
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    Quote Originally Posted by Turveyd
    A wagon wheel spoke is strong and won't compress like a thin metal spoke which will deform.
    But a wagon wheel is JUST a COMPRESSED COLUMN and not a pre-stressed (under tension) member. You need to read up on some principles.

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    Quote Originally Posted by nov0798
    It doesnt loose contact with the rim per se. If you have 500 lbs of force on the spoke in tension, and you place 300 lbs of vertical load on that spoke, you still have 200 lbs of tension on the spoke that is holding the nipple against the rim. Until you exceed the stressed value, then all is good!
    You're repeating what I said. He didn't get that either.

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    Quote Originally Posted by Mike T.
    But a wagon wheel is JUST a COMPRESSED COLUMN and not a pre-stressed (under tension) member. You need to read up on some principles.

    It's not me comparing a wagon wheel, totally different structure to a spoked wheel trying to prove a point.

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    Quote Originally Posted by Turveyd
    WHAT, so you where supporting the claims of increased lower spoke tension, but know claim, lower tension at the bottom, which is ofcourse correct and fine come on explain how a spoke with lower tension that none stressed can support weight.

    Come on go full on science on me, I can handle it!!
    I never said that tension increases in the lower spokes. I said the drop in tension is what supports the load. It's just like the tug-of-war example. The decrease in tension in the rope is what "pushes" you backward.
    I linked a great paper on structural analysis of a bike wheel. Read it, and if you are right in your theory, point out the flaw in that analysis.
    Quote Originally Posted by pvd
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    Quote Originally Posted by Mike T.
    You're repeating what I said. He didn't get that either.
    He provided an example, where the force didn't exceed the tension so it didn't move the nipple, we where talking about a force that does and yet the wheel doesn't collapse.

    Yes the spokes which are horizontal on a landing are also put under stress as the rim compresses top to bottom forcing the sides out, thats why im my test I wanted you to leave enough horizontal spokes in to keep the structure.

    With the bottom spokes removed you'd be surprised how strong the wheel still is, ofcourse flip the wheel the other way around and it becomes a noodle as the spokes fall in.

    I can't weight the wheel and take a photo have to wait till I've got a mate here to take the photo's.

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    Quote Originally Posted by Turveyd
    He provided an example, where the force didn't exceed the tension so it didn't move the nipple, we where talking about a force that does and yet the wheel doesn't collapse.
    Then your reading comprehension is bad as well as your understanding of tensioned wheel concepts.

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    Quote Originally Posted by meltingfeather
    I never said that tension increases in the lower spokes. I said the drop in tension is what supports the load. It's just like the tug-of-war example. The decrease in tension in the rope is what "pushes" you backward.
    I linked a great paper on structural analysis of a bike wheel. Read it, and if you are right in your theory, point out the flaw in that analysis.

    Yet again, you are confusing yourself with a totally different force, both sides aren't pulling.

    The decrease in rope tension, doesn't push you backwards, you push yourself backwards thats the difference because you haven't adapted quick enough to the less force thats required, no resemblence at all to spokes.

    Gravity is pushing the hub down, due to the weight of the bike / rider, yes both spokes are pulling on each other trying to keep the hub central via there tension, increasing the tension of the top, which the hub dangles from, decreasing the bottom both equally.

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    Sorry but if you don't understand how a game of tug of war works then you really shouldn't be attempting to talk science.

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    Quote Originally Posted by Turveyd
    Gravity is pushing the hub down, due to the weight of the bike / rider, yes both spokes are pulling on each other trying to keep the hub central via there tension, increasing the tension of the top, which the hub dangles from, decreasing the bottom both equally.
    Nope. This question has been asked and answered many times before. If you want to poke a hole in the well-established science, I provided a great paper for you to do it with.
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    The thing about using the internet and none scrutinized reports from likely failed university physic projects is you'll find what ever your looking for, both sides of the story, so it's kinda irrelevant.

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    Quote Originally Posted by Turveyd
    Sorry but if you don't understand how a game of tug of war works then you really shouldn't be attempting to talk science.
    the science is there in the link provided. rip away at it.
    i think an additional challenge for you besides the tricky concepts in pre-stressed structures will be approaching it with an open mind.
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    Quote Originally Posted by meltingfeather
    Nope. This question has been asked and answered many times before. If you want to poke a hole in the well-established science, I provided a great paper for you to do it with.

    It's only well established in your mind and the mind of others that heard it this way first from others who likely also just repeated it.

    I have a partially built wheel, which I know you won't accept as it's no longer a wheel, but trust me, the hub is being help up from the TOP!!!

    Question, what you hear for the sake of humanity, don't defend it, just cause you heard it that way first and don't want to accept being wrong.

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    Quote Originally Posted by meltingfeather
    the science is there in the link provided. rip away at it.
    i think an additional challenge for you besides the tricky concepts in pre-stressed structures will be approaching it with an open mind.

    He said with a totally closed mind.

    I'm a scientist you ??

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    Quote Originally Posted by Turveyd
    The thing about using the internet and none scrutinized reports from likely failed university physic projects is you'll find what ever your looking for, both sides of the story, so it's kinda irrelevant.
    find a source that shows that wheels hang from the upper spokes, then.
    scrutinize the report and find the fatal flaw.
    you asked for science, it has been provided. show the fault. i could not find any and I have read the report numerous times.
    claiming that the report is irrelevant because of a bunch of unsupported assumptions on your part is a cop out.
    Quote Originally Posted by pvd
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    Whoops, Sorry Mike T!

    Ok another anolgy(maybe)

    If you had a hub and a spokes that were stong enough(untensioned) to support the rider and no wheel, and the hub was laced with all the spokes, then obviously the bike would stand and could be ridden without the wheel, proving that the load is placed downward.

    https://www.google.com/imgres?imgurl...:0&tx=76&ty=60

    Also the wheel ultimately laced with all the spokes transfers the load to the bottom, exactly what an arch does. The load has to be transfered down. Even if it pulls on the top of the wheel, the arch transfers load around its outside down to the bottom.

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    Quote Originally Posted by meltingfeather
    find a source that shows that wheels hang from the upper spokes, then.
    scrutinize the report and find the fatal flaw.
    you asked for science, it has been provided. show the fault. i could not find any and I have read the report numerous times.
    claiming that the report is irrelevant because of a bunch of unsupported assumptions on your part is a cop out.

    Sorry but lets get REAL basic here, okay you think you can push something with rope, err no rope is for PULLING.

    Get a single strand of cotton tie it to your bike and using tension, you can pull your bike around, know try without touching the frame to push the bike!!

    Until you understand the basics, I really think you should stay away from the heavy stuff.

    Not that wheels are that heavy, very simple the wheel was after all invented shortly before you no doubt think the world was created.

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    Quote Originally Posted by Turveyd
    The thing about using the internet and none scrutinized reports from likely failed university physic projects is you'll find what ever your looking for, both sides of the story, so it's kinda irrelevant.
    Henri Gavin's work in Bicycle Wheel Patterns and Spoke Fatigue, which you discounted as "rubbish" is from a peer-reviewed and highly regarded scientific journal (ASCE Journal of Engineering Mechanics).
    He has a bachelor's in civil from Princeton, a Master's and PhD from Michigan, and is a structural professor at Duke. He is also a reviewer for many specialized structural scientific journals. Hardly a "failed university physics project," but don't let the facts get in the way of your assumptions.
    Quote Originally Posted by pvd
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    Quote Originally Posted by meltingfeather
    Henri Gavin's work in Bicycle Wheel Patterns and Spoke Fatigue, which you discounted as "rubbish" is from a peer-reviewed and highly regarded scientific journal (ASCE Journal of Engineering Mechanics).
    He has a bachelor's in civil from Princeton, a Master's and PhD from Michigan, and is a structural professor at Duke. He is also a reviewer for many specialized structural scientific journals. Hardly a "failed university physics project," but don't let the facts get in the way of your assumptions.


    The 1 you linked was crap, the 2nd one was better, not once did it say the lower spokes support the load, ofcourse you believe it does but NO IT DOES NOT!!

    Come on, lets get back to Tug of war game, and the rope pushes the person over, come on, explain this, is the rope frozen ??

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    Quote Originally Posted by Turveyd
    Sorry but lets get REAL basic here, okay you think you can push something with rope, err no rope is for PULLING.

    Get a single strand of cotton tie it to your bike and using tension, you can pull your bike around, know try without touching the frame to push the bike!!

    Until you understand the basics, I really think you should stay away from the heavy stuff.

    Not that wheels are that heavy, very simple the wheel was after all invented shortly before you no doubt think the world was created.
    this is a joke. it's you missing the fundamentals by being caught up and convinced by over-simplified "examples."
    since i have a master's in civil engineering and am a licensed professional engineer with training in structures, what are your qualifications as a "scientist" for commenting on pre-stressed structures and claiming that the whole field of structural engineering has gotten this wrong?
    the whole point of pre-stressing is to avoid a particular material or structural member's weakness in certain applications (like concrete in tension or thin steel wire in compression).
    in another missed inerpretation of an example by you, pulling a bike by a cotton thread is not a a pre-stressing situation.
    like i said, it is tricky. i say this as a person who has been through actual education on structures. calling names doesn't add to your credibility, and the gauntlet has been thrown with respect to your disproving the science. either you are for real and can back up what you say by discrediting actual peer-reviewed science, or you have no credibility.
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    Quote Originally Posted by meltingfeather
    this is a joke. it's you missing the fundamentals by being caught up and convinced by over-simplified "examples."
    since i have a master's in civil engineering and am a licensed professional engineer with training in structures, what are your qualifications as a "scientist" for commenting on pre-stressed structures and claiming that the whole field of structural engineering has gotten this wrong?
    the whole point of pre-stressing is to avoid a particular material or structural member's weakness in certain applications (like concrete in tension or thin steel wire in compression).
    in another missed inerpretation of an example by you, pulling a bike by a cotton thread is not a a pre-stressing situation.
    like i said, it is tricky. i say this as a person who has been through actual education on structures. calling names doesn't add to your credibility, and the gauntlet has been thrown with respect to your disproving the science. either you are for real and can back up what you say by discrediting actual peer-reviewed science, or you have no credibility.

    And I've flown to the mars twice, using just my arms and holding my breath really well, see you can claim to be anything on the internet.

    Sorry but someone with a back ground of that really, would not think the person falls over in a tug of war because the rope pushes them.

    Your peer-reviewed science, does not even mention where the load is supported, just the effects on the spokes as the wheel rotates around, so your linking science which doesn't even back up what your saying.

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    Quote Originally Posted by Turveyd
    Come on, lets get back to Tug of war game, and the rope pushes the person over, come on, explain this, is the rope frozen ??
    once you understand the tug-of-war example i think you may have a "eureka moment" with respect to bike wheels.
    the drop in tension in the rope is what causes the participant to move backward. he wasn't pushed, but his force countering the rope (a necessary condition of the pre-stressing) caused an imbalance when rope tension decreased. the rope "acts" as a rigid column with respect to the participant's motion (the rope shrinks according to it's elasticity, exactly as a compression member would, and the result is backward motion of the participant), but it never goes into compression due to the pre-stress load.
    enough with the overly simplified examples. blow a hole in the structural analysis paper (whichever you think is best). find a reliable source to back up your claim.
    i'm done with the back-and-forth until you come up with something worthwhile. when you do i'll be glad to discuss it further.
    Quote Originally Posted by pvd
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    Quote Originally Posted by meltingfeather
    once you understand the tug-of-war example i think you may have a "eureka moment" with respect to bike wheels.
    the drop in tension in the rope is what causes the participant to move backward. he wasn't pushed, but his force countering the rope (a necessary condition of the pre-stressing) caused an imbalance when rope tension decreased. the rope "acts" as a rigid column with respect to the participant's motion (the rope shrinks according to it's elasticity, exactly as a compression member would, and the result is backward motion of the participant), but it never goes into compression due to the pre-stress load.
    enough with the overly simplified examples. blow a hole in the structural analysis paper (whichever you think is best). find a reliable source to back up your claim.
    i'm done with the back-and-forth until you come up with something worthwhile. when you do i'll be glad to discuss it further.

    Once I understand LOL

    Creationists, got to hate them!!

    The person falls over, because he's pulling really hard, and his muscles can't stop pulling in time, so he continues to go that way, once you understand that, maybe you should question your religion.

    82% of americans are creationists, so good odds I'm right about this.

    Hey you started the personal attacks first!!!

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    Quote Originally Posted by meltingfeather
    once you understand the tug-of-war example i think you may have a "eureka moment" with respect to bike wheels.
    the drop in tension in the rope is what causes the participant to move backward. he wasn't pushed, but his force countering the rope (a necessary condition of the pre-stressing) caused an imbalance when rope tension decreased. the rope "acts" as a rigid column with respect to the participant's motion (the rope shrinks according to it's elasticity, exactly as a compression member would, and the result is backward motion of the participant), but it never goes into compression due to the pre-stress load.
    enough with the overly simplified examples. blow a hole in the structural analysis paper (whichever you think is best). find a reliable source to back up your claim.
    i'm done with the back-and-forth until you come up with something worthwhile. when you do i'll be glad to discuss it further.

    Ohhh just remember, NO WHERE in your link, does it say the load is supported anywhere, I've checked, so your bogusly claiming something, linking a thread to it and counting on no one will have the time or energy to read it to disprove it.

    Not 1 mention, idiot!!

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    Quote Originally Posted by Turveyd
    Your peer-reviewed science, does not even mention where the load is supported, just the effects on the spokes as the wheel rotates around, so your linking science which doesn't even back up what your saying.
    The results of the tests, which broadly confirm Pippard's analysis, make the prestressing behavior of the spoke/rim system clear. The rim does vey little to carry the load. It's main function is to provide the reaction system for the tensile prestress in the spokes, which as a result of the pretension, are able to carry significant compressive forces before they buckle."
    sure about that?
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  101. #101
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    Quote Originally Posted by meltingfeather
    sure about that?

    Yep, don't believe it, my stripped wheel says other wise.

    The nipples are not attached to the rim, any load would just force the nipple into inner tube, thankfully the other side stops them going to far, the nipples would have to be attached to the rim for any compression to work.

    Keep trying sucker!!

  102. #102
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    Quote Originally Posted by Turveyd
    Once I understand LOL

    Creationists, got to hate them!!
    that's kinda funny, because you're holding onto your belief out of faith, using all kinds of distracting tactics to steer the discussion away from logic.
    Quote Originally Posted by Turveyd
    Hey you started the personal attacks first!!!
    Just like the papers, the thread is here in black and white to confirm that you are wrong. Calling people idiots in all caps is not a personal attack?
    I have yet to make a personal attack. i understand that you think my and others pointing out your incorrect interpretation of structures is a personal attack. it is not. the substance of your argument is at issue, not anything about you personally. it is you who cannot differentiate the two.
    i'm still waiting to hear your qualifications for commenting on structures... and for you to point out where all of the conclusions from structural analysis by people who have been trained in it and do it for a living are wrong.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  103. #103
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    Quote Originally Posted by Turveyd
    Ohhh just remember, NO WHERE in your link, does it say the load is supported anywhere, I've checked, so your bogusly claiming something, linking a thread to it and counting on no one will have the time or energy to read it to disprove it.
    the thing with scientific papers is that they are written for a scientific audience, so they don't always hold your hand and walk you through the basics that form the fundamental understanding they're working from.
    Notice that there is no increase in strain (tension) in the spokes at the top in Figure 6 in the paper I linked or any of the graphical representations of spoke tension or strain in any studies on it?
    That's clue no. 1.
    Quote Originally Posted by Turveyd
    Not 1 mention, idiot!!
    classy.
    when logic fails, call names!!! (you forgot to hit caps lock)
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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    Quote Originally Posted by meltingfeather
    that's kinda funny, because you're holding onto your belief out of faith, using all kinds of distracting tactics to steer the discussion away from logic.

    Just like the papers, the thread is here in black and white to confirm that you are wrong. Calling people idiots in all caps is not a personal attack?
    I have yet to make a personal attack. i understand that you think my and others pointing out your incorrect interpretation of structures is a personal attack. it is not. the substance of your argument is at issue, not anything about you personally. it is you who cannot differentiate the two.
    i'm still waiting to hear your qualifications for commenting on structures... and for you to point out where all of the conclusions from structural analysis by people who have been trained in it and do it for a living are wrong.

    Nope a statement of fact, is never a insult, merely a statement of fact.

    You do not understand how a wheel structure works, you believe rope can push people are, yes push, if that is what you do for a living, you need to start looking for another career before someone realises this.

    Considerable compression, is a huge leap to the lower spokes support the load, huge leap, massive leap, I'd say sub 5% of the wheels strength is because of spoke compression.

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    Maybe we should all just agree that it really doesnt matter, just as long as the wheel works, which it does. So as the old saying goes, "lets not reinvent the wheel"!

  106. #106
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    Quote Originally Posted by meltingfeather
    the thing with scientific papers is that they are written for a scientific audience, so they don't always hold your hand and walk you through the basics that form the fundamental understanding they're working from.
    Notice that there is no increase in strain (tension) in the spokes at the top in Figure 6 in the paper I linked or any of the graphical representations of spoke tension or strain in any studies on it?
    That's clue no. 1.

    classy.
    when logic fails, call names!!! (you forgot to hit caps lock)

    you put 230lb's ( ME ) of weight onto a spoke shared between others and notice no increase in tension then the science is flawed, that defies all logic the dynamics of the wheel is creating bogus stress calculations.

    Bad Bad Science!!

  107. #107
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    A typical pre-tensioned 2.0mm straight gauged spokes can stretch up to 1.0mm in a bicycle wheel and still remain elastic like a rubber band. Most mild grades of steel, like a wire spoke, can be stretch and relaxed million of times without losing its elasticity (i.e. its ability to bounce back to its original shape after it is stretched, compressed or twisted). What I described in the previous sentence is the material’s fatigue cycle, which can be dramatically reduced if the material has a stress riser in its loading zone. A stress riser is large or small area of the material that has been stress beyond its elastic limit and to its yield point where the material can no longer bounce back and will quickly fracture if it is not unloaded. A dimple, a bend (spoke elbow), a cut (cut treads at the end of a spoke) and deformation (rolled treads at the end of a spoke or the mushroom head at the opposite end) are all examples of stress risers. The spokes at the bottom of the wheel do not buckle because they are stretched out (through tension) as much as 1.0mm and are compressed by a rider’s weight by about 0.1+/-mm. All of the other spokes that are not in the loading zone at the bottom of the wheel keep the 1, 2, 3 or 4 bottom spoke in tension when the rider’s weight is transmitted down as a compressive force through the spokes and the rim deflects or flattens out to further compress the bottom spokes. Think of this cycle as a rubber band analogy, where the rubber band is stretched to ten times its relaxed shape (say from 1 inch stretch out to 10 inches) and it is continuously de-tensioned down to 9” and back up to 10 inches. The rubber band never gets slack as long as its loading cycle doesn’t’ change by a large margin. Add to this rubber band analogy the very large unit strength of steel and the concept of a rider’s weight standing on the bottom spokes really comes together.

  108. #108
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    'Feather, methinks we're dealing with a Troll here. No-one with any intelligence would poo-poo proven science. Just because they can't grasp the concept of a wheel doesn't mean that they're right and engineering science got it all wrong. No-one "bright" enough to be able to use a computer would do that, so, from that, I'll conclude he's a Troll.


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    definately not a troll, but I do think you guys are total idiots and haven't got a clue what your on about and just making stuff up to try to sound smart, I guess most would buy it, but I'm sure as hell not.

    Tug of war, the person falls over cause the rope pushes them LOL kinda says it all really.

    And stop announcing your right and I'm wrong, you have 2 words in a entire article taken out of context your basing your entire arguement on and no logic what so ever.

  110. #110
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    Quote Originally Posted by Turveyd
    Tug of war, the person falls over cause the rope pushes them LOL kinda says it all really.
    it does say it all, since i specifically said the rope does not push, yet you distort and misrepresent what said to try and make some "point" while avoiding the real discussion. so i'd say, yeah, that sorta does sum it up: you misinterpreting yet another simple example and using it to call people idiots and recommend that they learn the basics. you're an IT guy? i guess that would explain why you didn't note any training or knowledge of structures. nice.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  111. #111
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    Quote Originally Posted by Mike T.
    'Feather, methinks we're dealing with a Troll here. No-one with any intelligence would poo-poo proven science. Just because they can't grasp the concept of a wheel doesn't mean that they're right and engineering science got it all wrong. No-one "bright" enough to be able to use a computer would do that, so, from that, I'll conclude he's a Troll.
    i'm with ya. our buddy here's got a pretty long history of being a know-it-all, loudmouth [email protected] on a few bike forums. made quite a reputation for himself, actually.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  112. #112
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    Quote Originally Posted by Turveyd
    Gravity is pushing the hub down, due to the weight of the bike / rider, yes both spokes are pulling on each other trying to keep the hub central via there tension, increasing the tension of the top, which the hub dangles from, decreasing the bottom both equally.
    Geez, leave a thread for a few hours and this is what happens.

    The tension changes are not equal at all. The only way the top tension increase is the same as the bottom tension decrease is if the rim is infinitely stiff, since that is the only way to transfer a force all the way at the bottom of the wheel all the way to the top. Rather, what happens in real life is that the bottom of the rim very slightly flat spots, which means the bottom spokes get a little bit shorter, hence they pull down less hard on the hub, which cancels out the external downwards load applied to the hub. The rest of the rim bulges out very very slightly, so the rest of the spokes increase in tension, but only by a tiny bit.
    The magic of pre-loaded structures is that the bottoms spokes don't push up on the hub, they pull down by less. The bottom spokes are still under tension, just less than before.



    Why won't you try the spoke plucking test on a functional wheel? It's so easy.
    Last edited by beanbag; 02-07-2011 at 08:54 PM.

  113. #113
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    Quote Originally Posted by meltingfeather
    sure about that?
    The results of the tests, which broadly confirm Pippard's analysis, make the prestressing behavior of the spoke/rim system clear. The rim does vey little to carry the load. It's main function is to provide the reaction system for the tensile prestress in the spokes, which as a result of the pretension, are able to carry significant compressive forces before they buckle."


    thought spokes don't see compressive forces?

  114. #114
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    Quote Originally Posted by beanbag
    Why won't you try the spoke plucking test on a functional wheel? It's so easy.
    because then he might have to rethink his belligerent insistence that he knows better.
    nice work, btw.
    *edit*
    wait... nevermind. i forgot that he already explained to all of us idiots that spoke tension measurements, whether absolute (tensiometer) or relative (plucking) are bogus, and can actually tell you that tension decreased when, in fact, it increased.
    yes... really.
    Last edited by meltingfeather; 02-07-2011 at 10:51 PM.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  115. #115
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    Unintended consequences....

    Tho this conversation is going round and round, the beating to death of it has helped a non-engineering type such as myself, slowly get my head around the concept.

    P

  116. #116
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    Quote Originally Posted by Mr.P
    Tho this conversation is going round and round, the beating to death of it has helped a non-engineering type such as myself, slowly get my head around the concept.

    P
    nice!
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  117. #117
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    Quote Originally Posted by peabody
    thought spokes don't see compressive forces?
    they don't go into compression... that is, they never (by design) lose all of the tension or see a positive compressive load.
    they do see compressive forces, and act as compression members would (shorten proportional to their elasticity). that's why the spokes at the bottom support the load and that's also the thing that twists people up.
    they think a thin steel wire can't support compression well, and it can't, so you add a massive pre-tension load to it so that when compressive forces are applied, the result is a drop in tension, but the spoke never goes into compression. in this way pre-stressing allows certain structural members to act as if they are in compression or tension without actually being. it's a shift in the equilibrium point.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  118. #118
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    Quote Originally Posted by meltingfeather
    they don't go into compression... that is, they never (by design) lose all of the tension or see a positive compressive load.
    they do see compressive forces, and act as compression members would (shorten proportional to their elasticity). that's why the spokes at the bottom support the load and that's also the thing that twists people up.
    they think a thin steel wire can't support compression well, and it can't, so you add a massive pre-tension load to it so that when compressive forces are applied, the result is a drop in tension, but the spoke never goes into compression. in this way pre-stressing allows certain structural members to act as if they are in compression or tension without actually being. it's a shift in the equilibrium point.
    At one time, I too, like Turv, believed that a hub hung from its spokes instead of sitting on them but it was you who provided the reasoning for the exact opposite to what I was hanging on to. My high school Physics knowledge took a beating that day. Turv is hanging onto his opinion of "remove some spokes and the hub does hang from the upper spokes and it can't sit on the lower ones" but his opinion has one massive glaring flaw - as soon as we remove enough spokes from the wheel to prevent all the spokes contributing to its integrity then we DON'T HAVE a bicycle wheel anymore - we just have a bunch of parts barely connected. They might as well be laying in their boxes and untensioned spokes, like Turv keeps banging on about, will carry no more compressive load than a few grams.

    He's failing to see that the weight of the bike and rider is responsible for flexing the piece of the rim that's touching the road and it's this action, and the corresponding lowering of the built-in tension of the spokes in that area, that is supporting the load. When the load becomes so great that the tension of these spokes becomes less than zero then we don't have a bicycle wheel anymore - we have the equivalent of a concertina or Turv's "wheel" that isn't a wheel.

  119. #119
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    Quote Originally Posted by peabody

    thought spokes don't see compressive forces?
    The spokes doesn't see a compressive force, but the rim does. Here's a diagram of a simplified 4 spoke wheel, with the rim divided up into 4 arches.



    The spoke is the red force that pulls up (tension). The two green arrows are the internal pre-load compressive forces that push inwards and down. These forces only exist if the rest of the wheel is laced up and tensioned. The black arrow is the ground pushing up. U can see that the forces are balanced. If the load on the wheel increases (black arrow gets bigger), then the red arrow gets shorter (tension decreases) and the green arrows get longer, and the forces still balance.

    The wheel segment is like an upside down arch bridge, held together by compressive pre-load.

  120. #120
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    Sorry never going to buy it.

    Yes there is a compression force in the rim, yes this will cause a egg shape the the horizontal spokes taking the tension and attempting to keep the wheel round, yes there will be some compression loading through the spokes as spokes have got more structure than my string / wire comparison ( Disco wheel was it ).

    Your data above the 3 diagrams of wheels, I completely agree with force wise, but no your target focused on 1 effect the lower compression, which although there and mysterous to you I guess, is playing very little in the strength of the wheel relative to the top spokes.

  121. #121
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    Quote Originally Posted by Turveyd
    Sorry never going to buy it.
    i predict that you'll be successful in remaining willfully ignorant as long as your heart desires.
    you can lead a horse to water and all that...
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  122. #122
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    Quote Originally Posted by meltingfeather
    I have yet to make a personal attack.
    Well that is certainly not a true statement.

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    Quote Originally Posted by meltingfeather
    they don't go into compression... that is, they never (by design) lose all of the tension or see a positive compressive load.
    they do see compressive forces,Not true self contratictory and act as compression members would (shorten proportional to their elasticity). that's why the spokes at the bottom support the load and that's also the thing that twists people up.
    they think a thin steel wire can't support compression well, and it can't, so you add a massive pre-tension load to it so that when compressive forces are applied, the result is a drop in tension, but the spoke never goes into compression.So they don't see compressive forces in this way pre-stressing allows certain structural members to act as if they are in compression or tension without actually being. it's a shift in the equilibrium point.

    Course some of those three spoked wonders do see compressive forces.

  124. #124
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    Quote Originally Posted by Turveyd
    Sorry never going to buy it.

    Yes there is a compression force in the rim, yes this will cause a egg shape the the horizontal spokes taking the tension and attempting to keep the wheel round, yes there will be some compression loading through the spokes as spokes have got more structure than my string / wire comparison ( Disco wheel was it ).

    Your data above the 3 diagrams of wheels, I completely agree with force wise, but no your target focused on 1 effect the lower compression, which although there and mysterous to you I guess, is playing very little in the strength of the wheel relative to the top spokes.
    What happens if the spokes have essentially zero tension when the wheel is on the stand, they generally are a little wobbly.

  125. #125
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    Quote Originally Posted by jeffscott
    Course some of those three spoked wonders do see compressive forces.
    true. Mavic's R-Sys wheels are also an exception (the spokes are designed to go into compression, and it worked out really well for them), but they don't fall into the category of pre-stressed, wire-spoked wheels that the OP or any of the analysis is focused on.
    and pre-tensioned members do see compressive forces without going into compression. it is not a contradiction, it is a fundamental principle of pre-stressed design.
    Last edited by meltingfeather; 02-08-2011 at 09:30 AM.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  126. #126
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    Quote Originally Posted by jeffscott
    Well that is certainly not a true statement.
    yes it was. the context is this thread, not your butthurt from however long ago that precipitated from your own instigation.

    shouldn't have clicked-through the view post link on this one. oh well...
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  127. #127
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    Quote Originally Posted by Turveyd
    yes this will cause a egg shape the the horizontal spokes taking the tension and attempting to keep the wheel round,
    The rim does not become oval. If it did, the top spokes would get shorter, and the top tension would go down, not up as you said. Can you provide a diagram of what you think the rim shape in a loaded wheel is, compared to unloaded?

    Quote Originally Posted by Turveyd
    but no your target focused on 1 effect the lower compression, which although there and mysterous to you I guess, is playing very little in the strength of the wheel relative to the top spokes.
    I am having difficulty parsing this statement. You agreed with the force diagrams. The bottom spokes are the ones that are at risk of going slack, which limits the strength of the wheel. Nothing much happens to the top spokes.

  128. #128
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    Quote Originally Posted by beanbag
    The rim does not become oval. If it did, the top spokes would get shorter, and the top tension would go down, not up as you said. Can you provide a diagram of what you think the rim shape in a loaded wheel is, compared to unloaded?



    I am having difficulty parsing this statement. You agreed with the force diagrams. The bottom spokes are the ones that are at risk of going slack, which limits the strength of the wheel. Nothing much happens to the top spokes.

    The tension in the horizontal spokes stop the wheel going Oval, a Wheel with spokes is the sum of it's parts there all working in different ways.

    the lower tension, until that becomes zero is still trying to pull the hub down, how can something thats trying to pull the hub down also be holding it up, yes it's pulling it down less relatively to the top is pulling it up, but pulling it down less relatively is NEVER holding it up.

    i predict that you'll be successful in remaining willfully ignorant as long as your heart desires.
    you can lead a horse to water and all that... ( that can surely apply to you aswell )

  129. #129
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    When did I ever say the bottom spokes push up?

    Why haven't you tried the spoke plucking test?

  130. #130
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    Quote Originally Posted by meltingfeather
    true. Mavic's R-Sys wheels are also an exception (the spokes are designed to go into compression, and it worked out really well for them), but they don't fall into the category of pre-stressed, wire-spoked wheels that the OP or any of the analysis is focused on.
    and pre-tensioned members do see compressive forces without going into compression. it is not a contradiction, it is a fundamental principle of pre-stressed design.

    Total BS buddy


    If a member sees an overall compressive force it is in compression

    If a member sees an overall tension force it is in tension....

    oh and if the result of the forces puts no stress on the memeber it is unstressed...

  131. #131
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    Quote Originally Posted by beanbag
    When did I ever say the bottom spokes push up?

    Why haven't you tried the spoke plucking test?

    Surely thats what a compression force is!!

    Plucking test ?? what is that supposed to achieve and why is it scientifically viable, IT ISn't there is a clue for you.

    Have you not tried my spoke removal test ??

    Your own logic, screams it's BS but you lot still keep going.

  132. #132
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    Quote Originally Posted by meltingfeather
    yes it was. the context is this thread, not your butthurt from however long ago that precipitated from your own instigation.

    shouldn't have clicked-through the view post link on this one. oh well...

    Why bother your statement was false...

    and your attitude confrontational..

  133. #133
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    Quote Originally Posted by Turveyd
    Surely thats what a compression force is!!

    Plucking test ?? what is that supposed to achieve and why is it scientifically viable, IT ISn't there is a clue for you.

    Have you not tried my spoke removal test ??

    Your own logic, screams it's BS but you lot still keep going.
    When did I ever say the spokes are under compressive force? Are you confusing me with somebody else?

    Plucking test tells you spoke tension, and will also tell you in 30 seconds or less that the top spoke tension doesn't increase as much as you think.

    I haven't tried your spoke removal test because it is retarded and isn't a non-invasive test of a loaded wheel.

  134. #134
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    Quote Originally Posted by jeffscott
    If a member sees an overall compressive force it is in compression
    true. but i didn't say "overall" or net positive compressive force. if a pre-tensioned member sees a compressive force lower than the pre-tension load, it sees a reduction in tension instead of a positive compression load.
    Once again... that's the whole point of pre-stressing.
    A quote from a structural analysis paper that I already cited, and which you apparently missed:
    The results of the tests, which broadly confirm Pippard's analysis, make the prestressing behavior of the spoke/rim system clear. The rim does vey little to carry the load. It's main function is to provide the reaction system for the tensile prestress in the spokes, which as a result of the pretension, are able to carry significant compressive forces before they buckle.
    If you want to learn about pre-stressed structures and their counter-intuitive performance and analysis, I encourage you to do that. I'd strongly suggest that you do if you want to call BS on published experts and trained professionals.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  135. #135
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    Quote Originally Posted by meltingfeather
    i predict that you'll be successful in remaining willfully ignorant as long as your heart desires.
    you can lead a horse to water and all that...
    A fine idiom fits here.

  136. #136
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    Quote Originally Posted by beanbag
    When did I ever say the spokes are under compressive force? Are you confusing me with somebody else?

    Plucking test tells you spoke tension, and will also tell you in 30 seconds or less that the top spoke tension doesn't increase as much as you think.

    I haven't tried your spoke removal test because it is retarded and isn't a non-invasive test of a loaded wheel.

    Tension is a weird thing, this is what is screwing up your theory, 100lb pressure both sides for instance, lower will drop to 50lb's and the top will only likely increase to 110lb's, thats the difference, 1mm of extra spoke stretch has to both sides, i can feel this just pushing on a wheel with full spokes not even on a bike.

    A simple test is retarded, yet a plucking test is relevant intestering!!

    Passes this list to a science mate who read it and thinks you lot are confused totally much like I think, had a nice long discussion about it.

    Compression on the rim and the tension from the spokes upper and sides keeping it together is how the wheel works in short.

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    A wheel isn't even a pre stressed structure, this is where your going wrong, a bridge as shown in the picture back a bit is a pre stressed structure a wheel is a suspension bridge, held by effectively spokes either side of a structure canceling each other out.

    Unless you understand the basics your going to lead down a path of myths which is what is happening here.

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    Quote Originally Posted by Turveyd
    Tension is a weird thing, this is what is screwing up your theory, 100lb pressure both sides for instance, lower will drop to 50lb's and the top will only likely increase to 110lb's, thats the difference, 1mm of extra spoke stretch has to both sides, i can feel this just pushing on a wheel with full spokes not even on a bike.
    Umm, isn't that what I said when I posted the 3 diagrams of the wheel?
    First you said the top tension change and bottom tension change are equal, and now you are saying they are not. I've always said that the top barely changes tension at all, and the bottom spoke has the big tension change.

    Now you are saying that the bottom spoke decreases in tension, yet it stretches 1mm?

    I think you are the one who is confused.

    When you "pushed on a wheel" that wasn't mounted on the bike, you pushed at the hub, and not the top, right?

  139. #139
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    Quote Originally Posted by Turveyd
    A wheel isn't even a pre stressed structure
    O. M. G.

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    Quote Originally Posted by beanbag
    Umm, isn't that what I said when I posted the 3 diagrams of the wheel?
    First you said the top tension change and bottom tension change are equal, and now you are saying they are not. I've always said that the top barely changes tension at all, and the bottom spoke has the big tension change.

    Now you are saying that the bottom spoke decreases in tension, yet it stretches 1mm?

    I think you are the one who is confused.

    When you "pushed on a wheel" that wasn't mounted on the bike, you pushed at the hub, and not the top, right?

    Actually if you read back, I said, the distance would be the same, oppositely ofcourse, the effect on the tension isn't the same, then you get the rim deforming at the bottom to, further weaking the lower, hopefully not out of tension, but there is ZERO chance those lower spokes give much upward support.

    At the hub yes!!

    If you push on the top of just a rim, then it egg shaped nicely, won't be a egg shame from the hub though, but can't see that without loosening off a lot of spokes, not got the time for that, snipping a few Mavic spokes and shooting them across the room on the other hand was fun

  141. #141
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    To further refine my rubber band analogy I posted yesterday afternoon, the hub is held in the center of the rim hoop by all of the equally tensioned spokes when it is unloaded. For simplicity let’s say that the wheel is laced with (36) spokes that were originally all 275mm long before they were tensioned in the wheel. With each of the (36) spokes laced and tensioned in the wheel to 120Kgf they all have stretched out to 276mm. Next let’s mount the wheel in the rear drop-outs and have a 200 pound rider sit on the seat. The rider’s 200 pound weight is transmitted down through the frame into the wheels axle and through the hub to the three bottom spokes, which all shrink by 0.1mm+/-. The three bottom spokes shrink by 1.0mm+/- because they are absorbing the rider’s weight above (axial load) and taking up the slack from the rims flat spot. The reaction of the ground pushing back up with an equal 200 pound force on the bottom of the rim causes the rim to bend/deflect/flatten-out and is responsable for the compression in the three bottom spokes as well. The remainder of the rim around the bottom load zone (at the flat spot) very slightly grows in diameter (more accurately bulges or deforms outward from the flat spot), which in-turn changes the length of the remaining (33) spokes by either +.001mm or -.001mm. These very very small changes in length of the (33) spokes (for the most part) cancel each other out and therefore can be viewed as unloaded or unaffected by the riders weight. In essence, the (33) unloaded spokes keep the hub centered in the rim hoop only—they do not support the rider.
    Getting back to my original question, how can an end user/consumer figure out if a wheel is strong enough to support his or her weight with a margin of safety? Most rim and wheel manufacturers do not specify the maximum weight their products can carry safely. Then there is the question of durability—conventional wisdom says that the more over built the wheel is (read stronger) the more durable it will be. Of course this paradigm is an over simplification because a super strong wheel can breakdown very quickly due to poor spoke quality and improper building techniques. For example, my old 2005 Mavic Crossroads with 24 spokes lasted for over two years without any issues while my OEM Mountain bike wheels with Mavic 117 rims and 32 spokes held up for six months before the spokes started breaking. So the Crossroad wheels were more durable but not stronger.

  142. #142
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    Quote Originally Posted by Turveyd
    Actually if you read back, I said, the distance would be the same, oppositely ofcourse, the effect on the tension isn't the same,
    How is this possible? If a spoke's length changes by +/- x, its tension has to change by +/- y. Change in tension is proportional to change in length.

  143. #143
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    Quote Originally Posted by bwalton
    Getting back to my original question, how can an end user/consumer figure out if a wheel is strong enough to support his or her weight with a margin of safety?
    Read post #30 again.

  144. #144
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    Quote Originally Posted by bwalton
    Getting back to my original question, how can an end user/consumer figure out if a wheel is strong enough to support his or her weight with a margin of safety?
    it depends on what you define as the margin of safety.
    Reliable determination of this requires some fairly advanced (for the typical wheel customer) analytical capability.
    Quote Originally Posted by bwalton
    Most rim and wheel manufacturers do not specify the maximum weight their products can carry safely. Then there is the question of durability—conventional wisdom says that the more over built the wheel is (read stronger) the more durable it will be. Of course this paradigm is an over simplification because a super strong wheel can breakdown very quickly due to poor spoke quality and improper building techniques. For example, my old 2005 Mavic Crossroads with 24 spokes lasted for over two years without any issues while my OEM Mountain bike wheels with Mavic 117 rims and 32 spokes held up for six months before the spokes started breaking. So the Crossroad wheels were more durable but not stronger.
    the answer is that most wheels are over-built and if you want to ride the edge, find a competent, quality builder or develop the skills yourself. wheelbuilding takes some care, but it is not rocket science.
    Last edited by meltingfeather; 02-09-2011 at 08:34 PM.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  145. #145
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    Quote Originally Posted by beanbag
    O. M. G.
    fer real.
    multiple exclamation points - check
    name calling - check
    feeble grasp of the queen's tongue - check
    avoidance of the issues - check
    all caps - check
    long history of internet [email protected] - check
    conclusion = TROLL
    Last edited by meltingfeather; 02-09-2011 at 08:59 AM.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  146. #146
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    Quote Originally Posted by meltingfeather
    long history of internet [email protected] - check

  147. #147
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    Quote Originally Posted by meltingfeather
    ............rocket science.
    Ofer fluck's sake.........I can feel a Turv argument coming on............

  148. #148
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    Quote Originally Posted by beanbag
    How is this possible? If a spoke's length changes by +/- x, its tension has to change by +/- y. Change in tension is proportional to change in length.

    That is another poor incorrect assumption, the spokes are all pretty much at max tension / rim eyelet capacity so ofcourse it doesnt increase to much more, why your assumpton is incorrect the top doesnt change much the bottom does so it's the bottom despite a large spoke tension drop which is doing all the work, FAIL!!!!

    p.s. not a troll, that is another error your making and a personal attack, just much cleverer than you you can't even handle having a adult debate.

  149. #149
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    Quote Originally Posted by Turveyd
    That is another poor incorrect assumption, the spokes are all pretty much at max tension / rim eyelet capacity so ofcourse it doesnt increase to much more, why your assumpton is incorrect the top doesnt change much the bottom does so it's the bottom despite a large spoke tension drop which is doing all the work, FAIL!!!!
    Spokes are still within the linear part of the stress strain curve, even if they are at "max tension" as specified by the rim manufacturer.

    Quote Originally Posted by Turveyd
    p.s. not a troll, that is another error your making and a personal attack, just much cleverer than you you can't even handle having a adult debate.
    I seriously think you have me confused with somebody else because I'm not making any personal attacks. Why don't you take it out on Meltingfeather and Mike T?


    Since I can't really tell what you are saying anyway, let's try this.
    Why don't you just assume for now that an unloaded wheel has 100kg spoke tension all around, and u tell me what is the spoke tension and rim deflection at 12, 3, 6, and 9 o-clock on a loaded wheel?

  150. #150
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    Quote Originally Posted by beanbag
    Spokes are still within the linear part of the stress strain curve, even if they are at "max tension" as specified by the rim manufacturer.



    I seriously think you have me confused with somebody else because I'm not making any personal attacks. Why don't you take it out on Meltingfeather and Mike T?


    Since I can't really tell what you are saying anyway, let's try this.
    Why don't you just assume for now that an unloaded wheel has 100kg spoke tension all around, and u tell me what is the spoke tension and rim deflection at 12, 3, 6, and 9 o-clock on a loaded wheel?
    Sorry I might of quoted yours, but wasn't aimed at you, on the basis you haven't you can assume it's not at you but the others with there troll BS.

  151. #151
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    Quote Originally Posted by beanbag
    Spokes are still within the linear part of the stress strain curve, even if they are at "max tension" as specified by the rim manufacturer.



    I seriously think you have me confused with somebody else because I'm not making any personal attacks. Why don't you take it out on Meltingfeather and Mike T?


    Since I can't really tell what you are saying anyway, let's try this.
    Why don't you just assume for now that an unloaded wheel has 100kg spoke tension all around, and u tell me what is the spoke tension and rim deflection at 12, 3, 6, and 9 o-clock on a loaded wheel?

    Esimated results would be :-

    12, 110 - 120
    3 and 9, 105 - 110
    6, likely 50 allowing for rim deflection.

    Sorry but to me, less tension in a spoke which we all agree on, there is less tension right ?? is not because it's load bearing, yes it's pulling down on the hub less which helps the hub stay up.

    But there is never any compression and it's not pushing.


    Think, just 2 spokes fitted, 1 at 12, 1 at 6, 100lb each :- ( really strong rim that isn't deflecting for ease for calcs )

    Apply a 50lb load at the hub, the 12 spoke will load upto 125 say, the 6 will drop to 75, the wheel still has 200'b of loading

    The hub with the extra load is still in the centre of the wheel due to the 2 changes of forces.

    at 100lb's, 12 = 150lb's, 6 = 50's

    at 200lb's, 12 = 200lb's, 6 = 0lb.s

    At 300lb's. 12 = 300lb's, 6 = 0lb's can't have negative and the spoke is no longer in the rim, wheel has failed, hub is no longer in the centre.




    Put the weight upto 200lb's and do the maths again :-



    The top spoke will have 200lb's of force

  152. #152
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    Quote Originally Posted by Turveyd
    you can't even handle having a adult debate.
    funny... calling people idiots in all caps is definitely adult behavior. of course you might think that if you're in 4th grade and jimmy in your "maths" class says his mommy does it. a mixing bowl helmet and cardboard box space ship don't make you an astronaut.

    bike wheels aren't prestressed structures, changes in spoke length are not proportional to tension, your busted wheel somehow proves all this... i just can't keep up. next thing you know you're going to blow all of our minds by "proving" bike wheels aren't round.

    and saying all of your BS leads one to think you're a troll is not a personal attack, merely a statement of fact.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  153. #153
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    Quote Originally Posted by meltingfeather
    bike wheels aren't prestressed structures
    What's the techie term for them then? Pre-tensioned structures?

  154. #154
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    Quote Originally Posted by meltingfeather
    funny... calling people idiots in all caps is definitely adult behavior. of course you might think that if you're in 4th grade and jimmy in your "maths" class says his mommy does it. a mixing bowl helmet and cardboard box space ship don't make you an astronaut.

    bike wheels aren't prestressed structures, changes in spoke length are not proportional to tension, your busted wheel somehow proves all this... i just can't keep up. next thing you know you're going to blow all of our minds by "proving" bike wheels aren't round.

    and saying all of your BS leads one to think you're a troll is not a personal attack, merely a statement of fact.

    Your never going to see it, I see why your seeing it the way you do but it's just wrong, for some reason it's stuck in your head that spokes can be load bearing because of the magic of prestressed.

    Suspension bridges suspend from the top for a reason, a wheel of this sort is a suspension bridge, not the sort of bridge you put the photo up a few pages back.

  155. #155
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    Quote Originally Posted by Turveyd
    not the sort of bridge you put the photo up a few pages back.
    'Feather didn't. But comprehension is also not one of your strong points. You've proved that before.

  156. #156
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    Quote Originally Posted by Mike T.
    What's the techie term for them then? Pre-tensioned structures?
    both are right. pre-tensioned is more specific. pre-stressed could also be compression (like in concrete design). our genius compadre here just "dropped" that gem... bike wheels aren't even pre-stressed structures.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  157. #157
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    Your also completely focused on the strength of the wheel provided by the spokes with no consideration for the Rim, the weight is supported by the rim at the bottom and I can assure you from riding different rim strengths / weights with similar spoke setups the rim is vitally important. More so than the spokes as long as the spokes can take the tension.

    If this wasn't the case, Disco wheels laced with Wire would not work.

  158. #158
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    Wow, mysterious pre-stressed, pre-tensioned dubble-poast removed.

  159. #159
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    Quote Originally Posted by Mike T.
    'Feather didn't. But comprehension is also not one of your strong points. You've proved that before.

    OMG I must be wrong, because I didn't go back and check who posted the picture.



    I'd expect this behavour from 8year olds not alledgey grown men!!



    My wheel with spokes removed PROVES this, fancy words prove nothing, you LOSE!!!


    But carry on preaching bad science to all, good job, I give up, Americans!!

  160. #160
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    Quote Originally Posted by Turveyd
    I'd expect this behavour from 8year olds not alledgey grown men!!
    There ya go again - making bad assumptions. I won't even mention that you can't even spell.

  161. #161
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    Quote Originally Posted by Turveyd
    Your never going to see it, I see why your seeing it the way you do but it's just wrong, for some reason it's stuck in your head that spokes can be load bearing because of the magic of prestressed.

    Suspension bridges suspend from the top for a reason, a wheel of this sort is a suspension bridge, not the sort of bridge you put the photo up a few pages back.
    you are right. i'm not going to see it because i can't deny reality the way you can. if i thought the way you do i could never have become an engineer. the fact is that you are dead wrong. almost everything you have said is dead wrong, from your ill-founded logic to your "maths" to your ridiculous conclusions.
    you can kick and scream and call names all you like, but it doesn't change the facts.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  162. #162
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    Quote Originally Posted by Mike T
    I won't even mention that you can't even spell.

    Then why did you?

  163. #163
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    Quote Originally Posted by Mike T.
    There ya go again - making bad assumptions. I won't even mention that you can't even spell.

    Canada in your case, but your really old you still likely believe in stuff we've later since disproved.

    I just don't care tbh.


    All you have to do is take a few spokes out of a wheel then you'll notice how little effect the lower spokes have, just 4 spokes will do, but why prove yourself wrong.

  164. #164
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    Quote Originally Posted by meltingfeather
    you are right. i'm not going to see it because i can't deny reality the way you can. if i thought the way you do i could never have become an engineer. the fact is that you are dead wrong. almost everything you have said is dead wrong, from your ill-founded logic to your "maths" to your ridiculous conclusions.
    you can kick and scream and call names all you like, but it doesn't change the facts.

    thats you opinion, my opinion is exactly the same about you, sadly there is zero point trying to have a intelligent debate which has no interest in listening to counter arguement.

    I have considered your counter arguement, discussed it at length with a science person and sorry none of it holds water.

  165. #165
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    A wheel is round. If its not round, its an oval and is no longer a wheel.
    an Mavic Crossride's support 200 pounds safely?
    Yes. I think that answers the question without all the math and *****ing and moaning going on in this thread.

  166. #166
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    Quote Originally Posted by Turveyd
    thats you opinion, my opinion is exactly the same about you, sadly there is zero point trying to have a intelligent debate which has no interest in listening to counter arguement.

    I have considered your counter arguement, discussed it at length with a science person and sorry none of it holds water.
    the boys over at bikemagic had you figured out quite a while back, eh?

    Quote Originally Posted by mtbmatty
    hans what you an dylan arguing about then?
    Quote Originally Posted by Nobby
    What everyone argues with Dylan about.

    The fact that he is never wrong - although I heard that one time, long ago, he thought he might be wrong but it turned out he was mistaken......
    Quote Originally Posted by Mike S
    I enjoy winding the idiot up, love the way he tries to attribute quotes to me. He's the most stupid person I've ever conversed with and believe me some real idiots frequent my LBS!
    Quote Originally Posted by Dan : /
    Mike, the guy is suprisingly normal in real life you know. I think a lot of the misunderstanding comes from applying pure logic to Dylan's thinking..it just doesn't work ;-)
    Quote Originally Posted by Nobby
    I used to find it mildly amusing but now I think it's an issue of "internet persona out of control". It's my belief that he's actually not an insane, over-opinionated eejit but sometimes what starts as a bit of fun careers out of control usually with disastous effects.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  167. #167
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    Yep there as dumb as you, I hate the BS they come up with, guess what been proven right about absolutely every single argument I've had with them. Good example.


    Also proves just how much of a low life you are, trying to discredit someone else to save face because you can't actually prove that your right can you ?? nope not in the slightest, wonder why that is hmmmm ohhh your WRONG thats it.

  168. #168
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    Quote Originally Posted by Turveyd
    thats you opinion, my opinion is exactly the same about you, sadly there is zero point trying to have a intelligent debate which has no interest in listening to counter arguement.

    I have considered your counter arguement, discussed it at length with a science person and sorry none of it holds water.
    I have a hard time empathizing with your point of view simply due to the fact that when you were asked to present some form of scientific justification (studies/papers, etc.), you never took the opportunity to offer any such foundation/basis for your understanding.

    I've read through the pro-offered links from Melting Feather, and the information contained within includes straight forward conclusions. He has also posted on several occassions in the past with additional references, which I have also read through.

    I understand that each person is entitled to their own opinions, but I take issue when people present opinions as Factual information.

    If you were able to present scientifically themed case study work that purports your suppositions, I'd be open minded to read them and re-consider. Having spent time over the years perusing the available info readily available to the masses, I'm going to guess that you may have a difficult time doing so.

  169. #169
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    They haven't provided a paper, which clearly states that the lower spokes hold up the wheel, there papers make no mention of this, why would a paper be made as it's fair obvious to most people this is not the case.

    I invite them to a: find a paper which states this which isn't jibberish and b: explain how a spoke can support a compression load when neither side is attached as in the Mavic wheel ( this should be funny )

  170. #170
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    Infact if it was the case, it would be very easy to find as that would be a pretty amazing and confusing thing.

    As there isn't, we'll put it down as confusion and error.

  171. #171
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    Quote Originally Posted by Turveyd
    They haven't provided a paper, which clearly states that the lower spokes hold up the wheel, there papers make no mention of this, why would a paper be made as it's fair obvious to most people this is not the case.

    I invite them to a: find a paper which states this which isn't jibberish and b: explain how a spoke can support a compression load when neither side is attached as in the Mavic wheel ( this should be funny )
    i don't think anybody is buying that you're open to anything that you don't already think, which would require denial of all logic and understanding... unless you've successfully convinced yourself of that.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  172. #172
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    Quote Originally Posted by meltingfeather
    i don't think anybody is buying that you're open to anything that you don't already think, which would require denial of all logic and understanding... unless you've successfully convinced yourself of that.
    That would another mistake your making, I'm not your average thicko, I don't care what people think, but I HATE BS and this is BS.

    If you could come up with something, anything tangible I'd listen, but you haven't, your group not just has posted conjecture followed by personal attacks.



    And you have also proved that you are 1 of the lowest forms of life on this planet, well done!!


    Hint: I always win, because I always have a smoking bullet, keep digging!!

  173. #173
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    What I am asking for is some advice on what combination of components make a wheel sufficiently strong enough to carry a 205 pound rider like myself over at least 3 years (3000 miles) without failure or the need for constant maintenance.
    I have rebuilt many front and rear OEM wheels with new spokes and new hubs and have learned that durability is primarily a function of: 1. Spoke quality, 2. rim trueness and roundness and 3. wheel building techniques, which can be categorized as: A. uniform spoke tension that is within 10 to 15% of the rims yield point, B. keeping the spokes untwisted so they don’t unscrew when ridden on (greasing the rim holes and spoke threads help minimize the wind-up and galling the rim), C. correcting the spoke line and D. stress relieving the spokes.
    That being said, these rebuilt back wheels do slowly deteriorate under my weight and require minor re-truing every 3 or 4 months. The shallow rims with less spokes require more frequent maintenance than the tall rims with more spokes. I suppose dripping some flow-able lock-tight down in the nipple threads would prevent the nipples from working themselves loose every 3 to 4 months but I don’t like the idea of gumming up the spoke threads.
    I am not looking for a specific product recommendation-I am looking for a formula that will produce strong wheels that are very durable—after all that was the whole point of this exercise . For example, the author of The Bicycle Wheel states that (36) 14/15 Ga. swaged spokes laced to a deep sectioned rim provides the best balance of strength, light weight and durability possible. What throws me off are the road bike aero wheels and the mountain bike wheels (like the Mavic Crossrides) with low spoke counts that survive for years under a heavy rider without their rims going out of true. Their rim sections are not really that much deeper than a convention wheel’s rim with many more spokes so how do they hold up so well? I work with a road biker who weighs 240 pounds and has been riding on his (18) spoked Mavic Ksyrium wheels for six years without any problems whatsoever—how can this be? Likewise a number of members have reported similar results with their Crossride wheels in this post as well. Obviously the answer is that these custom designed wheels with low spoke counts are strong enough to support a heavy rider but are manufactured is such a way to eliminate stressors in the components that lead to durability issues and early failures.

  174. #174
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    Actually do you know what, I'm BORED so BANG have the smoking bullet!!

    http://hea-www.harvard.edu/~fine/opi...bikewheel.html

    ( yes that is Harvard LOL )

    Wrong!
    Many people have used this description to explain how it is that the lower spokes are the ones that support the bicycle wheel. But you have to be careful to examine what is really happening.

    The "compression" of the bicycle spokes is really a mathematical fiction. They are compressing only in that there is less tension than there was before. Relative to the starting (pre-tensioned) state, they have compressed, but relative to the totally slack state, the spokes are still in tension. In other words the lower spokes which are described as being in "compression" are still pulling downwards on the hub. Clearly, pulling downwards can not have the effect of holding up.

    Only the upper spokes are actually pulling upwards on the hub. This is why I still say, without any doubt, that the hub hangs from the upper spokes. Oddly this does not contradict the following statement, that the lower spokes play the most dynamic role in supporting the load.

    As far as the true test, of cutting away spokes to see which ones are more or less important, I haven't tried it (I can't afford to, can you?). I suspect that you could get away with cutting more lower spokes than you could upper spokes (when there is a load on the hub). But because of the pretensioning process, all spokes play some role in supporting the hub at all times.

    Next time, I suggest that a OPEN mind is kept, thankyou and goodbye, TOOLS!!!

  175. #175
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    Quote Originally Posted by Turveyd
    Actually do you know what, I'm BORED so BANG have the smoking bullet!!

    http://hea-www.harvard.edu/~fine/opi...bikewheel.html

    ( yes that is Harvard LOL )

    Wrong!
    Many people have used this description to explain how it is that the lower spokes are the ones that support the bicycle wheel. But you have to be careful to examine what is really happening.

    The "compression" of the bicycle spokes is really a mathematical fiction. They are compressing only in that there is less tension than there was before. Relative to the starting (pre-tensioned) state, they have compressed, but relative to the totally slack state, the spokes are still in tension. In other words the lower spokes which are described as being in "compression" are still pulling downwards on the hub. Clearly, pulling downwards can not have the effect of holding up.

    Only the upper spokes are actually pulling upwards on the hub. This is why I still say, without any doubt, that the hub hangs from the upper spokes. Oddly this does not contradict the following statement, that the lower spokes play the most dynamic role in supporting the load.

    As far as the true test, of cutting away spokes to see which ones are more or less important, I haven't tried it (I can't afford to, can you?). I suspect that you could get away with cutting more lower spokes than you could upper spokes (when there is a load on the hub). But because of the pretensioning process, all spokes play some role in supporting the hub at all times.

    Next time, I suggest that a OPEN mind is kept, thankyou and goodbye, TOOLS!!!
    My understanding was somewhat parallel, until a while ago this exact debate was exchanged on MTBR and Melting Feather referenced several resources that offered an introspective to the whole genre of topic material. From there I went as deep as I could from one resource citing another, I tried to gobble up all the info that was available.

    Without an engineering background, a lot of the concepts were initially a struggle for me, my first exposure to which were within cross referenced resources, requiring more and more reading on my part.

    I kept getting stuck mentally on this concept that the nipple nor the spoke head are not permanently attached to anything. The engineering examples of diagrams of columns etc., seemed non-applicable to me, I had a though time thinking, "but the spoke isn't supported the same way the column is". Additionally, for each new principle that I ran across, I was running the risk of shoe horning the entire scope of the topic into one frame of my mind, becuase I didn't have the step by step exposure to all of the related educational background. My understanding "light bulb" switched "on" when I started looking at the wheel and the force vectors as a system, a whole entity. Subtract a few spokes here or there, and you no longer have a system, it doesn't matter if you only clip one spoke, nor that the wheel still may look the same, the system is no longer functional due to missing parts. The force vectors at play can be applied this direction or that, with a bicycle wheel it seems like you can slap them on any way you want to prove your point of view. (That's official non-engineering talk, by the way).

    My own personal understanding, developed from my online research, but in large part influenced by the pro-offered links by Melting Feather, and I have learned that the lower spokes are the ones undergoing fluctuations in tension most measurably as the wheel rotates, they are the ones doing the actual work, and also thanks to the aforementioned examples, I understand why their tensions fluctuate.

    Feel free to disagree, I'm not trying to influence anyone's one understanding of things. I just felt like sharing my own personal (and challenging) exploration into this exciting world of how things work. The best part about bicycle wheels, is that built in conventional form, are superbly strong and well equipped to function without knowing why.

  176. #176
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    Quote Originally Posted by CFoster
    My understanding was somewhat parallel, until a while ago this exact debate was exchanged on MTBR and Melting Feather referenced several resources that offered an introspective to the whole genre of topic material. From there I went as deep as I could from one resource citing another, I tried to gobble up all the info that was available.

    Without an engineering background, a lot of the concepts were initially a struggle for me, my first exposure to which were within cross referenced resources, requiring more and more reading on my part.

    I kept getting stuck mentally on this concept that the nipple nor the spoke head are not permanently attached to anything. The engineering examples of diagrams of columns etc., seemed non-applicable to me, I had a though time thinking, "but the spoke isn't supported the same way the column is". Additionally, for each new principle that I ran across, I was running the risk of shoe horning the entire scope of the topic into one frame of my mind, becuase I didn't have the step by step exposure to all of the related educational background. My understanding "light bulb" switched "on" when I started looking at the wheel and the force vectors as a system, a whole entity. Subtract a few spokes here or there, and you no longer have a system, it doesn't matter if you only clip one spoke, nor that the wheel still may look the same, the system is no longer functional due to missing parts. The force vectors at play can be applied this direction or that, with a bicycle wheel it seems like you can slap them on any way you want to prove your point of view. (That's official non-engineering talk, by the way).

    My own personal understanding, developed from my online research, but in large part influenced by the pro-offered links by Melting Feather, and I have learned that the lower spokes are the ones undergoing fluctuations in tension most measurably as the wheel rotates, they are the ones doing the actual work, and also thanks to the aforementioned examples, I understand why their tensions fluctuate.

    Feel free to disagree, I'm not trying to influence anyone's one understanding of things. I just felt like sharing my own personal (and challenging) exploration into this exciting world of how things work. The best part about bicycle wheels, is that built in conventional form, are superbly strong and well equipped to function without knowing why.

    Nah it's a 50year old myth generated by bad science, I'm sure there teachers likely taught them it, they can see a spoke tension drop but can't explain it, obviously it's because the rim is distorting and the upper spokes are under more strain, for some reason someone said those lower spokes support the hub / bike and it's hard to forget a myth once you've learnt it.;

    All they are doing is pulling down less, which helps the top spokes take the strain.

    The Rim is the structural component reinforced hugely by the spokes, it's the compression of the rim which is taking the weight, whats why people use the same spoke / hub layout but with DH rims for DHing, if they could use 100gram rims + 48 spokes they would do.

    Mavic Crossride wise, the 07 models could take it cause they've got heavy strong rims and the 24spokes run at seriously high tension and those bladed spokes aren't that light either, thankfully the hubs are pretty light and some people get away with less which is more about riding style, Crossride on the rear is fine locally, take it to the peaks and ride my fav easy but rocky descent and rear crossride trashed in no time.

    Spokes are strictly pulling devices!!!

  177. #177
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    Quote Originally Posted by Turveyd
    Spokes are strictly pulling devices!!!
    Then I doubt you'd be up for the notion that in a rear wheel there are pulling and pushing spokes?


  178. #178
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    Quote Originally Posted by Mike T.
    Then I doubt you'd be up for the notion that in a rear wheel there are pulling and pushing spokes?


    As you referenced rear wheel only, I presume you are refering to power transference through the spokes, then what your doing is twisting the hub relative to the rim when you put power down.


    Spokes never PUSH, they merely PULL Less. It's a relative difference.


    You can't just say the tension drops in the lower spokes so this must be holding it up, without some kind of real explanation why, you haven't got a real explaination because this isn't happening.

    Now say sorry, learn from this, keep an open mind and move on!!

  179. #179
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    Quote Originally Posted by Turveyd
    Nah it's a 50year old myth generated by bad science, I'm sure there teachers likely taught them it, they can see a spoke tension drop but can't explain it, obviously it's because the rim is distorting and the upper spokes are under more strain, for some reason someone said those lower spokes support the hub / bike and it's hard to forget a myth once you've learnt it.;
    so you believe the spoke tension drop that is seen in the bottom spokes, but for some reason you think the same measuring devices applied to the top spokes give bogus information...
    like you, tom fine has no knowledge or training in structures. like you, he uses flawed logic to arrive at false conclusions. like you, his proclamations do not prove anything except that he doesn't understand the system. unlike you, he seems to know that bike wheels ARE pre-tensioned structures. woops... i guess his rant doesn't really support your position after all.
    i know you don't have an open mind, and i know you are not interested in learning about bike wheels... that much you have proven. there's essentially one hump you have to get over to be able to understand it, and CFoster did a great job of explaining it.
    it's much older than 50 years, but since you're making up everything you've said, i guess you didn't think that would hurt either, eh?
    Chris - i didn't know that mtbr discussions and my posts in particular had started you on that path. that's cool.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  180. #180
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    Quote Originally Posted by meltingfeather
    so you believe the spoke tension drop that is seen in the bottom spokes, but for some reason you think the same measuring devices applied to the top spokes give bogus information...
    like you, tom fine has no knowledge or training in structures. like you, he uses flawed logic to arrive at false conclusions. like you, his proclamations do not prove anything except that he doesn't understand the system. unlike you, he seems to know that bike wheels ARE pre-tensioned structures. woops... i guess his rant doesn't really support your position after all.
    i know you don't have an open mind, and i know you are not interested in learning about bike wheels... that much you have proven. there's essentially one hump you have to get over to be able to understand it, and CFoster did a great job of explaining it.
    it's much older than 50 years, but since you're making up everything you've said, i guess you didn't think that would hurt either, eh?
    Chris - i didn't know that mtbr discussions and my posts in particular had started you on that path. that's cool.
    Cfoster, did a great job of being brain washed by you and then passing it on nothing more, this is sad, this is why myths are so hard to kill.

    You'll dismiss anything that doesn't fit into your view, you have the closed mind, next to impossible to get people to change there mind.

    Lets review the facts here :-

    1. neither of the links you've provided actually mention the lower spokes support the weight, 2 coincidental words your clinking to.
    2. Harvard trained students disagree with you.
    3. You, have no explaination of how these lower spokes support the weight, other than "compression" you might aswell use the words " Yellow Pixies"


    So after dismissing all evidence you drop to childish, it's been longer than 50years WOW really like I care, I do not know the date the myth was started or care, but there was a lot of bad science back then, things have moved on, sadly things are getting worse these days not better, any none critical thinking is just bad for humanity, please think for yourself and be objective.


    Try removing spokes!!
    Try adding 4 spokes to a rim, gluing them to the rim and seeing what happens when you apply a load to them.




    Come on no.3 explain it, in detail!!

  181. #181
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    Quote Originally Posted by meltingfeather
    so you believe the spoke tension drop that is seen in the bottom spokes, but for some reason you think the same measuring devices applied to the top spokes give bogus information...
    like you, tom fine has no knowledge or training in structures. like you, he uses flawed logic to arrive at false conclusions. like you, his proclamations do not prove anything except that he doesn't understand the system. unlike you, he seems to know that bike wheels ARE pre-tensioned structures. woops... i guess his rant doesn't really support your position after all.
    i know you don't have an open mind, and i know you are not interested in learning about bike wheels... that much you have proven. there's essentially one hump you have to get over to be able to understand it, and CFoster did a great job of explaining it.
    it's much older than 50 years, but since you're making up everything you've said, i guess you didn't think that would hurt either, eh?
    Chris - i didn't know that mtbr discussions and my posts in particular had started you on that path. that's cool.

    Sorry, I'd go google your enemies and see what there BSing about you, but I'm not 8 and I have a life.

    Sorry, but you really don't get lower than that, 2 of the people linked are actually mates and the other 2 I'd kill on site just to do the world a service.


    p.s. are you sure you want to keep going, I have bigger and better smoking bullets.

    You may still believe your BS, but I guess the others on here will be seeing you for the true low life which you is.

  182. #182
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    Quote Originally Posted by Turveyd
    Lets review the facts here :-

    1. neither of the links you've provided actually mention the lower spokes support the weight, 2 coincidental words your clinking to.
    like i said, scientific papers don't usually hold your hand through the obvious.
    Quote Originally Posted by Turveyd
    2. Harvard trained students disagree with you.
    tom fine neither went to harvard nor is a student. you are making stuff up again. surprise surprise.
    a whole field of experts and trained professionals disagree with you.
    Quote Originally Posted by Turveyd
    3. You, have no explaination of how these lower spokes support the weight, other than "compression" you might aswell use the words " Yellow Pixies"
    I have, and the research that has been cited demonstrates it. You are ignorant by choice. There is nothing I can do about that.

    Quote Originally Posted by Turveyd
    So after dismissing all evidence you drop to childish, it's been longer than 50years WOW really like I care, I do not know the date the myth was started or care, but there was a lot of bad science back then, things have moved on, sadly things are getting worse these days not better, any none critical thinking is just bad for humanity, please think for yourself and be objective.
    Finite element analysis, which many have now done on bike wheels, demonstrates exactly what you refuse to accept. It wasn't around 50 years ago. It is a relatively modern analytical tool that you apparently know nothing about.
    Quote Originally Posted by Turveyd
    Try removing spokes!!
    Try adding 4 spokes to a rim, gluing them to the rim and seeing what happens when you apply a load to them.

    Come on no.3 explain it, in detail!!
    It's been explained in a number of ways and research demonstrating how it works it has been provided for you to read (you may need this).
    Like I said, you will remain ignorant as long as you chose to.
    i got a chuckle out of the brainwashing comment, btw. conspiracy theorists are always amusing.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  183. #183
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    Quote Originally Posted by Turveyd
    Sorry, I'd go google your enemies and see what there BSing about you, but I'm not 8 and I have a life.

    Sorry, but you really don't get lower than that, 2 of the people linked are actually mates and the other 2 I'd kill on site just to do the world a service.
    that really hurt your feelings, did it? sorry about that, but you made your fairly widespread reputation that's easy to find, not me.
    Quote Originally Posted by Turveyd
    p.s. are you sure you want to keep going, I have bigger and better smoking bullets.
    bigger and better than fall-on-its-face fail i'd certainly like to see. let's have it.
    Quote Originally Posted by Turveyd
    You may still believe your BS, but I guess the others on here will be seeing you for the true low life which you is.
    funny, because people seem to be learning by this, despite your beligerent ranting.
    Last edited by meltingfeather; 02-09-2011 at 06:30 PM.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  184. #184
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    [QUOTE=meltingfeather]like i said, scientific papers don't usually hold your hand through the obvious.

    tom fine neither went to harvard nor is a student. you are making stuff up again. surprise surprise.
    a whole field of experts and trained professionals disagree with you.

    I have, and the research that has been cited demonstrates it. You are ignorant by choice. There is nothing I can do about that.


    Finite element analysis, which many have now done on bike wheels, demonstrates exactly what you refuse to accept. It wasn't around 50 years ago. It is relatively modern science that you apparently know nothing about.
    Quote Originally Posted by Turveyd
    Try removing spokes!!
    Try adding 4 spokes to a rim, gluing them to the rim and seeing what happens when you apply a load to them.


    It's been explained in a number of ways and research demonstrating how it works it has been provided for you to read (you may need this).
    Like I said, you will remain ignorant as long as you chose to.
    i got a chuckle out of the brainwashing comment, btw. conspiracy theorists are always amusing.

    Refering to Tom like you know him LOL


    I'm sorry, but you really are a braindead worthless piece of ****.

    You've been proven wrong, you can't answer no.3 you know what to do, it begins and F and ends with F!!

    Goodbye you sore LOSER!!

  185. #185
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    Quote Originally Posted by Turveyd
    Refering to Tom like you know him LOL
    uh... you linked his website, and apparently got confused because it's hosted at a harvard.edu domain and you didn't bother to read anything on the site except what you wanted to see. how would you prefer that i refer to him?
    Quote Originally Posted by Turveyd
    I'm sorry, but you really are a braindead worthless piece of ****.
    no need for apologies. i think it's you that needs some consolance. name calling is for children. adults are typically not bothered by it, as i am not bothered by you.
    Quote Originally Posted by Turveyd
    You've been proven wrong, you can't answer no.3 you know what to do, it begins and F and ends with F!!

    Goodbye you sore LOSER!!
    you already said that once, and i'm not believing anything you say at this point, so... we'll see you back here in five? great. ta ta!
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  186. #186
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    Wanker!!!

  187. #187
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    Quote Originally Posted by Turveyd
    Wanker!!!
    four minutes... close enough for me.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  188. #188
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    And still dodging no.3 cause you have no explaination for it.

    Goodbye LOSER!!

    If anyone is reading this which I doubt, he LOST, don't listen to a word he says on anything, he's not a what ever he claims to be just a troll.

  189. #189
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    Quote Originally Posted by Turveyd
    And still dodging no.3 cause you have no explaination for it.

    Goodbye LOSER!!

    If anyone is reading this which I doubt, he LOST, don't listen to a word he says on anything, he's not a what ever he claims to be just a troll.
    just... can't... let... go...
    the thing about my words is that they are clear, spelled correctly, organized into sentences, do not involve childish emotional outbursts, and are backed up by the sources I have provided.
    all you've got is flawed logic, a small repetoire of basic insults, and the caps lock and exclamation point keys.
    it's not a win/lose situation. the point was to try and educate you. everybody failed in that, but it wasn't for lack of effort.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  190. #190
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    DODGE again!! no.3!!!

    These are sources that make no reference to the lower spokes supporting the weight in any way shape or form, I'd just like everyone reading to remember that, hey just make random stuff up and people will believe anything if the spelling and grammar are correct.

    Sorry but isn't searching and posting crap like you did, kinda against the site rules ?? can't we have you banned, after all your not teaching anyone anything thats true.

    p.s. actually quite proud of my repution I kick ass and I'm always proven right.

    GOODBYE for the final time!!

  191. #191
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    Quote Originally Posted by Turveyd
    DODGE again!! no.3!!!
    everything is still right here in the thread. if you think i'm going to waste my time earnestly trying to explain something (again), you are mistaken (again). now watching a troll flounder and get flustered at his own game...
    Quote Originally Posted by Turveyd
    These are sources that make no reference to the lower spokes supporting the weight in any way shape or form,
    same story (still)
    Quote Originally Posted by Turveyd
    I'd just like everyone reading to remember that,
    if you think anyone's buying what you're selling you might give the thread a quick skim.
    Quote Originally Posted by Turveyd
    hey just make random stuff up and people will believe anything if the spelling and grammar are correct.
    this is funny, because other than the reference to another non-technical guy who tries like you do to refute established science with flawed, simplistic logic, you expect everyone to believe what you say i guess based on your credibility, which is nil. i, on the other hand, have taken time to try and explain things as they are understood by a whole field of professionals and provide peer-reviewed science that actually supports what i'm saying. making stuff up seems to be your specialty. harvard student, pre-tensioned structures, "maths"... any of that ring a bell?
    Quote Originally Posted by Turveyd
    Sorry but isn't searching and posting crap like you did, kinda against the site rules ?? can't we have you banned, after all your not teaching anyone anything thats true.
    got a source to back up your claim? didn't think so. discussion of issues and referencing credible sources are in no way against the rules. your posts, however, violate arguably four forum rules, sometimes simultaneously. if you need help finding the rules, they're here. you're welcome.
    Quote Originally Posted by Turveyd
    p.s. actually quite proud of my repution I kick ass and I'm always proven right.
    i'm sure you are (assuming you mean reputation). you've been at the same game for years. you can think that reality is dictated by what you say, and you may be successful in maintaining that illusion for yourself, but nobody else is convinced.
    Quote Originally Posted by Turveyd
    GOODBYE for the final time!!
    i call BS (again).
    Last edited by meltingfeather; 02-09-2011 at 08:41 PM.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  192. #192
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    Quote Originally Posted by Turveyd
    DODGE again!! no.3!!!

    These are sources that make no reference to the lower spokes supporting the weight in any way shape or form, I'd just like everyone reading to remember that, hey just make random stuff up and people will believe anything if the spelling and grammar are correct.

    GOODBYE for the final time!!
    Turveyd,

    Disagreeance spurs progress. I sense that there has developed some hostility, but its an acceptable byproduct of individuals expressing their thoughts. I'm only addressing you at the moment, not becuase of the aforementioned little "life tid-bit" but for this thought.

    I think it's difficult to uphold both an open mind, interested in all the facts, as well as insist that another individual must completely refute a particular/singular point of argument that you're interested in, in this case your sporadic reference no. 3.

    With regards to my process of self-education regarding the resources that Melting Feather contributed, it took me several days (atleast) to read through as much as I could. There's just tons of cross indexed info that can keep your head spinning 'til perpetuity. To this day I'm still very interested in this topic, and consider myself open minded to new ideas, if they have merit. Where I'm going with this is, well, I think that it takes more than a simple insistence that transfers the burden of proof from your shoulders unto another's to usurp your idea's value of merit over their's, which is what's happening with your insistence to no. 3, (and once or twice before with other requests for disproof).

    As with all science, it is the scientific mind that naturally insists to disprove their own ideas first before presenting them for review from their peers.

    With regards to your statement that I have been brainwashed, feel free to feel that way if you'd like. If you've read Ayn Rand (and others) you've been exposed to the concept that there exists very few individually creative thinkers in the world. By some perverse application of statistical probability, why should I be any different, right? Hence the merit of scientific application to scientific principles, the goal being to establish truths so that others may follow more closely to the truth.

    I'm all ears. My perception in the principles that Melting Feather presents with clarity are pretty solidified, naturally I am hard to sway, but as an astutute business man, I've learned to keep my ears open, especially to ideas with merit.

    Off topic to the above reply, but on topic with the original post, if my memory serves me correct regarding 2007 Crossrides specifically, I'd avoid them. The spokes are pretty heavy duty, but then again I believe they fall into that 'generic' stainless wire provider category, I won't say anything else. Feel free to amend that info as necessary.

  193. #193
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    Quote Originally Posted by Turveyd
    Actually do you know what, I'm BORED so BANG have the smoking bullet!!

    http://hea-www.harvard.edu/~fine/opi...bikewheel.html

    ( yes that is Harvard LOL )
    If you read that paper, that is his OPINION, and not fact! He has no more qualifications than anyone else on this board. Oh and his page is just hosted on a Harvard server. Hes actually a programmer, that works for the Smithsonian located at Harvard. DUH!

    No BANG because there is no gun, and your bullet is definitely not smoking!!

    And his resume, well not exactly a scientist,and cycling is his interest! If your taking his word as gold because his interest is cycling, then that should make some of these guys on this board friggen Einstein when it comes to cycling physics.

    http://hea-www.harvard.edu/~fine/Me/resume.html

    NEXT!
    Last edited by nov0798; 02-10-2011 at 01:01 AM.

  194. #194
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    Quote Originally Posted by Turveyd
    Esimated results would be :-

    12, 110 - 120
    3 and 9, 105 - 110
    6, likely 50 allowing for rim deflection.

    Sorry but to me, less tension in a spoke which we all agree on, there is less tension right ?? is not because it's load bearing, yes it's pulling down on the hub less which helps the hub stay up.

    But there is never any compression and it's not pushing.
    Ok, it's good that we mostly agree on the spoke tensions, even though that's not what you said earlier:

    Gravity is pushing the hub down, due to the weight of the bike / rider, yes both spokes are pulling on each other trying to keep the hub central via there tension, increasing the tension of the top, which the hub dangles from, decreasing the bottom both equally.
    But OK, that's in the past now.

    I think your hangup with Mr. Meltingfeather is that he used the words "compression" and "bottom spokes" in the same sentence, which is confusing. Nobody ever said that the bottom spokes are under compression. Rather, they help the rim take a compressive force by lowering their own tension. I think this part you would agree on. Didn't he try to explain that with the two people pulling a rope, and one of them pulls "less hard"?

    Think, just 2 spokes fitted, 1 at 12, 1 at 6, 100lb each :- ( really strong rim that isn't deflecting for ease for calcs )

    Apply a 50lb load at the hub, the 12 spoke will load upto 125 say, the 6 will drop to 75, the wheel still has 200'b of loading

    The hub with the extra load is still in the centre of the wheel due to the 2 changes of forces.

    at 100lb's, 12 = 150lb's, 6 = 50's

    at 200lb's, 12 = 200lb's, 6 = 0lb.s

    At 300lb's. 12 = 300lb's, 6 = 0lb's can't have negative and the spoke is no longer in the rim, wheel has failed, hub is no longer in the centre.
    That's the same as the middle example of the 3 wheels I showed, and I said that it only works if the rim is infinitely stiff, which you also said. In real life, the rim is not infinitely stiff and the top tension doesn't increase like in your example.

    I will now explain why your "test" of a wheel with most of the spokes removed is flawed. If you remove about half the spokes (from 9 to 3 o'clock), then the spoke at 6 o'clock has no tension on it because there is no opposing spoke. (Even the spokes at 9 and 3 o'clock have very little tension because the rim ovalizes out.)

    So if you put the wheel with the spokes on the bottom and press down, the spokes will collapse immediately because a spoke with no tension can't take compression. Well, that's nothing new. If you put the wheel with the spokes up and press down, the top spoke will develop a tiny bit of tension before the unsupported bottom of the rim collapsed. So your test proves nothing except that a unsupported rim is stronger than a unsupported spoke. What does this have to do with a real wheel?

    As for "the bottom spokes support the wheel" vs "a wheel hangs from the top spokes", as long as you have the spoke tensions right, you can argue the semantics with Mr. Meltingfeather all you want. I will point out that it is kind of dumb to say that the hub hangs from the top spokes, because it also "hangs" just as much from the side spokes, and also "hangs upside down" from the bottom spokes. When you apply a load to the hub, the wheel doesn't "hang any harder" from the top spokes. (only barely)

  195. #195
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    Quote Originally Posted by Turveyd
    I always win, because I always have a smoking bullet
    nice

  196. #196
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    Quote Originally Posted by beanbag
    Ok, it's good that we mostly agree on the spoke tensions, even though that's not what you said earlier:



    But OK, that's in the past now.

    I think your hangup with Mr. Meltingfeather is that he used the words "compression" and "bottom spokes" in the same sentence, which is confusing. Nobody ever said that the bottom spokes are under compression. Rather, they help the rim take a compressive force by lowering their own tension. I think this part you would agree on. Didn't he try to explain that with the two people pulling a rope, and one of them pulls "less hard"?



    That's the same as the middle example of the 3 wheels I showed, and I said that it only works if the rim is infinitely stiff, which you also said. In real life, the rim is not infinitely stiff and the top tension doesn't increase like in your example.

    I will now explain why your "test" of a wheel with most of the spokes removed is flawed. If you remove about half the spokes (from 9 to 3 o'clock), then the spoke at 6 o'clock has no tension on it because there is no opposing spoke. (Even the spokes at 9 and 3 o'clock have very little tension because the rim ovalizes out.)

    So if you put the wheel with the spokes on the bottom and press down, the spokes will collapse immediately because a spoke with no tension can't take compression. Well, that's nothing new. If you put the wheel with the spokes up and press down, the top spoke will develop a tiny bit of tension before the unsupported bottom of the rim collapsed. So your test proves nothing except that a unsupported rim is stronger than a unsupported spoke. What does this have to do with a real wheel?

    As for "the bottom spokes support the wheel" vs "a wheel hangs from the top spokes", as long as you have the spoke tensions right, you can argue the semantics with Mr. Meltingfeather all you want. I will point out that it is kind of dumb to say that the hub hangs from the top spokes, because it also "hangs" just as much from the side spokes, and also "hangs upside down" from the bottom spokes. When you apply a load to the hub, the wheel doesn't "hang any harder" from the top spokes. (only barely)

    Sorry hadn't really given spoke tension / loads much thought before, I was still refining my science, you know keeping a open mind, learning, adapting not being closed mind.

    The problem is you immediate associate, lower spokes losing tension as being a indicator of it's supporting the weight above it, this is a leap of faith and has zero real science, its what you've learnt, it's what you believe, but it's simply not logic, sadly you likely learned this from MF!! ( Apt initials )

    The lower spokes, don't even get into a compression state, which is good cause they'd be spearing your tubes and tubes won't give much compression support before going BANG, they merely get into a lower tension state as you can plainly see from your data.


    And in all this, you've completely discounted the Rim, not 1 mention, isn't the rim a reasonably important part of a wheel ?? I'd say YES!!!

  197. #197
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    Quote Originally Posted by Turveyd
    The problem is you immediate associate, lower spokes losing tension as being a indicator of it's supporting the weight above it, this is a leap of faith and has zero real science, its what you've learnt, it's what you believe, but it's simply not logic, sadly you likely learned this from MF!! ( Apt initials )
    I didn't learn my wheel mechanics from MF (even though we happen to agree on this subject) and I never used the word "support" to describe the function of the bottom spokes.

    And in all this, you've completely discounted the Rim, not 1 mention, isn't the rim a reasonably important part of a wheel ?? I'd say YES!!!
    I believe I mentioned the word "rim" 6 times in my above reply, one of them highlighted.

  198. #198
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    Quote Originally Posted by CFoster
    Turveyd,

    Disagreeance spurs progress. I sense that there has developed some hostility, but its an acceptable byproduct of individuals expressing their thoughts. I'm only addressing you at the moment, not becuase of the aforementioned little "life tid-bit" but for this thought.

    I think it's difficult to uphold both an open mind, interested in all the facts, as well as insist that another individual must completely refute a particular/singular point of argument that you're interested in, in this case your sporadic reference no. 3.

    With regards to my process of self-education regarding the resources that Melting Feather contributed, it took me several days (atleast) to read through as much as I could. There's just tons of cross indexed info that can keep your head spinning 'til perpetuity. To this day I'm still very interested in this topic, and consider myself open minded to new ideas, if they have merit. Where I'm going with this is, well, I think that it takes more than a simple insistence that transfers the burden of proof from your shoulders unto another's to usurp your idea's value of merit over their's, which is what's happening with your insistence to no. 3, (and once or twice before with other requests for disproof).

    As with all science, it is the scientific mind that naturally insists to disprove their own ideas first before presenting them for review from their peers.

    With regards to your statement that I have been brainwashed, feel free to feel that way if you'd like. If you've read Ayn Rand (and others) you've been exposed to the concept that there exists very few individually creative thinkers in the world. By some perverse application of statistical probability, why should I be any different, right? Hence the merit of scientific application to scientific principles, the goal being to establish truths so that others may follow more closely to the truth.

    I'm all ears. My perception in the principles that Melting Feather presents with clarity are pretty solidified, naturally I am hard to sway, but as an astutute business man, I've learned to keep my ears open, especially to ideas with merit.

    Off topic to the above reply, but on topic with the original post, if my memory serves me correct regarding 2007 Crossrides specifically, I'd avoid them. The spokes are pretty heavy duty, but then again I believe they fall into that 'generic' stainless wire provider category, I won't say anything else. Feel free to amend that info as necessary.

    CFOSTER,

  199. #199
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    Quote Originally Posted by CFoster
    Turveyd,

    Disagreeance spurs progress. I sense that there has developed some hostility, but its an acceptable byproduct of individuals expressing their thoughts. I'm only addressing you at the moment, not becuase of the aforementioned little "life tid-bit" but for this thought.

    I think it's difficult to uphold both an open mind, interested in all the facts, as well as insist that another individual must completely refute a particular/singular point of argument that you're interested in, in this case your sporadic reference no. 3.

    With regards to my process of self-education regarding the resources that Melting Feather contributed, it took me several days (atleast) to read through as much as I could. There's just tons of cross indexed info that can keep your head spinning 'til perpetuity. To this day I'm still very interested in this topic, and consider myself open minded to new ideas, if they have merit. Where I'm going with this is, well, I think that it takes more than a simple insistence that transfers the burden of proof from your shoulders unto another's to usurp your idea's value of merit over their's, which is what's happening with your insistence to no. 3, (and once or twice before with other requests for disproof).

    As with all science, it is the scientific mind that naturally insists to disprove their own ideas first before presenting them for review from their peers.

    With regards to your statement that I have been brainwashed, feel free to feel that way if you'd like. If you've read Ayn Rand (and others) you've been exposed to the concept that there exists very few individually creative thinkers in the world. By some perverse application of statistical probability, why should I be any different, right? Hence the merit of scientific application to scientific principles, the goal being to establish truths so that others may follow more closely to the truth.

    I'm all ears. My perception in the principles that Melting Feather presents with clarity are pretty solidified, naturally I am hard to sway, but as an astutute business man, I've learned to keep my ears open, especially to ideas with merit.

    Off topic to the above reply, but on topic with the original post, if my memory serves me correct regarding 2007 Crossrides specifically, I'd avoid them. The spokes are pretty heavy duty, but then again I believe they fall into that 'generic' stainless wire provider category, I won't say anything else. Feel free to amend that info as necessary.

    CFOSTER,

    Some times the papers you read will be bad science they will be based on bad logic to start with, where they look to prove something then make a leap of faith.

    MF can not explain how the spokes support anything, take that as a indication that something is missing. Neither can he point out in his own links where they claim support other 2 random words he's clinging to.


    Keep an open mind, question what you are being taught!!




    Smoking Gun doh!! knew it sounded wrong!!

  200. #200
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    Quote Originally Posted by Turveyd
    CFOSTER,

    Some times the papers you read will be bad science they will be based on bad logic to start with, where they look to prove something then make a leap of faith.

    MF can not explain how the spokes support anything, take that as a indication that something is missing. Neither can he point out in his own links where they claim support other 2 random words he's clinging to.

    Keep an open mind, question what you are being taught!!
    he had the mental capacity to read and understand for himself. you are asking him to question what he has learned based on your feeble logic and inability to get past one concept that you are clinging to. you have provided nothing to support any of your ridiculous claims.
    your argument is what is flawed logic, and if you had read the papers, you would see there are no leaps of faith in the scientific method. the FEA analyses and conclusions are actual research/science.
    Quote Originally Posted by Turveyd
    Smoking Gun doh!! knew it sounded wrong!!
    that ain't the only thing.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

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