Do 29er's have a Real Advantage???- Mtbr.com
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  1. #1

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    Idea! Do 29er's have a Real Advantage???

    OK...I'll set myself up for this. I rode a Cyclo-cross bike for the first time last fall and it was faster than stink climbing a hill. At first I thought it was the fact that it weighed 18lbs, but I got to thinkin'. Could the 700c wheels have anything to do with it? Everyone says I'm wrong but let me present this.

    If you are in the same gears on a 26" and a 29" wheeled bike. Everytime you turn the crank the distance the wheel travels is different. Let's say you are in a gear where 1 crank turn results in 1 turn of the cassette. For every crank turn, a 26" bike will travel (pi x d = 3.14x26") 81.64". However, the 29er will go 91.06" or 10" further with the larger wheels.

    Now the argument I get is that the 29er is not necessarily faster because of the additional effort required due to the larger torque arm of the wheel. In other words, rocks and general frictional resistance create a larger force because they act further out on a 29" wheel (Torque=ForcexDistance). But is it a direct relationship???

    My argument is that although the Torque created by "friction" is greater, the rolling resistance is less because the larger diameter rolls over impediments easier. So there is an advantage when it comes to speed.

    Also a 29'er will weigh a bit more because it has larger wheels and tires. But my sense is you may pick up at most an additional pound.

    So let the discussion begin. Do 29ers have an inherent advantage over a 26" bike based on the Wheel size? Are cyclo-cross bikes fast because of the 700c wheels and the inherent geometry or is it just weight that is involved. If they do have an advantage then why does NORBA and others allow Cyclocross and 29er's to compete head up against 26" bikes??? Shouldn't they have a weight penalty???

    Have at it!!!

  2. #2
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    The short answer is: yes. The long answer is: yes.
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  3. #3
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    holy crap you must have taken some pretty heavy engineering courses
    you just went way over my head
    #1 NORBA elite singlespeed racer 30-34 age group

  4. #4
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    Do you do when from one moment to another your wheels increase in size? You just shift back. The longer distance per crank rotation is near irrelevant, unless you come "short" with s 20-34t granny gear on a 26" bike already.

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    Quote Originally Posted by Cloxxki
    Do you do when from one moment to another your wheels increase in size? You just shift back. The longer distance per crank rotation is near irrelevant, unless you come "short" with s 20-34t granny gear on a 26" bike already.
    Cloxxki, why do you say the crank rotation is irrelevant??? If you're gaining 10" everytime you throw the cranks in the same gear, then you are picking up something. I think the issue is can you pedal a 29er in the same gear as a 26er on a given slope? Some argue that you can't because the increase in torque due to the wheel size will catch up to you in the end, but I don't buy it.

    It's interesting that everyone points out that 29er's are "smoother" but no one picks up on the circumference issues. Again, I'm surprised NORBA let's them and 700c bikes compete without a handicap. But then again, maybe there isn't that big of an advantage. Still 10" every stroke would certainly make my girlfriend happy

  6. #6
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    say what???

    Quote Originally Posted by dugodugo
    It's interesting that everyone points out that 29er's are "smoother" but no one picks up on the circumference issues. Again, I'm surprised NORBA let's them and 700c bikes compete without a handicap. But then again, maybe there isn't that big of an advantage. Still 10" every stroke would certainly make my girlfriend happy
    the difference in circumference and the perceived benefits, from longer, more tractable contact patch to gentler angle of approach with obstacles, is one of the thing that the rabid church of 29 choir here is constantly banging home...

    also, stating that there isn't necessarily a gear handicap going to a bigger wheel, that you gain a miraculous 10" of forward motion for every wheel rotation without any extra effort, is kind of presumptuous. my 26" ss has a 35x18 gear on it. the redline moncog 29 i just got in to test has a 32x18. they feel pretty close in pedal speed for a given ground speed. however, the monocog sticks better, longer, before breaking traction. whereas the 26" coconino can be lumped up from a stall a tiny bit easier. if i ran a 35x18 on the moncog, it would kill me (in fact, i ran a 34x18 on a kelly 29 at the 2000 cream puff and the resultant psychological damage from that was brutal enough to scare me away from both ss and 29 for a few years)...

    for reference: 34x18x29"=54.77" gear. 32x18x29=51.55". 35x18x26=50.55"

  7. #7
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    People, people, when calculating gear inches to the 1/100", do at least use 26.5". The rim size difference is 2.5", not 3"!!

    Check the FAQ thread for the real advantages and disadvantages, theoretic, real, or far-fetched.

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    Good job! Thanks for the input

    Quote Originally Posted by MtotheF
    also, stating that there isn't necessarily a gear handicap going to a bigger wheel, that you gain a miraculous 10" of forward motion for every wheel rotation without any extra effort, is kind of presumptuous. my 26" ss has a 35x18 gear on it. the redline moncog 29 i just got in to test has a 32x18. they feel pretty close in pedal speed for a given ground speed. however, the monocog sticks better, longer, before breaking traction. whereas the 26" coconino can be lumped up from a stall a tiny bit easier.
    Way cool...thanks for the input....this is real world stuff. So you are saying that you can really feel the difference of the torque reaction from a 29er??? I've never ridden one so I'm a newbie at this. I understand what you are saying about the contact patch, traction, angle of attack and all of that....it's the torque reaction I always wondered about.

    Now about NORBA...I guess I'm thinking that yes there is a "torque penalty" but does it balance out the rotational gain??? I hope you understand what I am getting at. The torque "may" catch up to you in the end, but if the course is relatively flat or it's undulating enough where you can catch your second wind on the downhills, ultimately you will have quite an advantage on a Cross Bike or 29er..

  9. #9
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    six of one, half dozen of another

    Quote Originally Posted by dugodugo
    Way cool...thanks for the input....this is real world stuff. So you are saying that you can really feel the difference of the torque reaction from a 29er??? I've never ridden one so I'm a newbie at this. I understand what you are saying about the contact patch, traction, angle of attack and all of that....it's the torque reaction I always wondered about.

    Now about NORBA...I guess I'm thinking that yes there is a "torque penalty" but does it balance out the rotational gain??? I hope you understand what I am getting at. The torque "may" catch up to you in the end, but if the course is relatively flat or it's undulating enough where you can catch your second wind on the downhills, ultimately you will have quite an advantage on a Cross Bike or 29er..
    for me, it's both good and bad. i love the way they roll out, and they definitely hold momentum. but i don't like the fragility of the wheels and tires compared to similar weight 26" stuff, and i don't entirely love the way they behave in technical terrain. many on here feel differently.

    per racing, talking with travis brown recently, he said that he and JHK were doing side by side comparisons last year with identically set up 26 and 29 bikes, and that whenever they swapped off, regardless of terrain, the 29 rider would pull away. for what that's worth.

    cloxxi, don't be so pedantic. 26, 26.5, whatever. there is enough variability in tire size that gear inch measurements are at best rough. how do you know the diameter of the 26" tire i was running? fwiw, i'll remember to bring my tape measure whenever i ride from here on out, if it'll make you happier...

  10. #10
    Eric the Red
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    Advantage: 29er

    My 29er is ridden all the time.
    My 26er hangs forgotten in the garage.
    My 29er is the irresistable force and my 26er is the immovable object.

  11. #11
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    Have you ever seen a monster truck show/race?...
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  12. #12
    Eric the Red
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    Quote Originally Posted by Rootberry
    Have you ever seen a monster truck show/race?...
    Ha! Somebody's sig here says people who don't understand 29ers are the people who take a Ford Ranger to a monster truck rally. Something like that anyway.

  13. #13

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    I guess he somehow missed the big stone tablets that commanded everyone to purge their lives of all things 26 and worship at the altar of the 29er or risk being smited by the gods. Jeez, people -- sure 29ers roll a little better, but they aren't magic carpets, fer cryin' out loud.

  14. #14
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    Quote Originally Posted by Li'l Bastard
    I guess he somehow missed the big stone tablets that commanded everyone to purge their lives of all things 26 and worship at the altar of the 29er or risk being smited by the gods. Jeez, people -- sure 29ers roll a little better, but they aren't magic carpets, fer cryin' out loud.
    But they do grow hair....

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  15. #15

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    Good job!

    Quote Originally Posted by MtotheF
    for me, it's both good and bad. i love the way they roll out, and they definitely hold momentum. but i don't like the fragility of the wheels and tires compared to similar weight 26" stuff, and i don't entirely love the way they behave in technical terrain. many on here feel differently.

    per racing, talking with travis brown recently, he said that he and JHK were doing side by side comparisons last year with identically set up 26 and 29 bikes, and that whenever they swapped off, regardless of terrain, the 29 rider would pull away. for what that's worth.
    ...
    Thanks dude...that is helpful. I could see what you're saying about technical terrain. In a rock garden the larger wheel is going to have a bigger impact on the steering force felt in the bars as you bang your way through it and take side hits. That makes a lot of sense.

    So in a racing environment it does sound like the 29er's have an advantage on a course that is not straight up hill (like the Angel Fire World Cup Course...talk about straight up!!!). I had a sense that was the case....I wonder why NORBA hasn't figured that out yet. Last year's NORBA Finale was won by a guy on a Crossbike for cryin' out loud.

    Hey edo....loved your comment....

    "My 29er is the irresistable force and my 26er is the immovable object."

    I have a Ti HT Airborne LS that I'm playing around with right now. Weighs about 22lbs. I'm looking for a B-29 and I figure if I can build it up at around 23-24lbs it would be real sweet. Just waiting for the component selection (tires, forks, etc) to get a little more developed.....

    Keep the big wheels rollin'

    Dugo

  16. #16

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    Tale of the power meter

    Put on a power meter...or do some basic physics equations.

    Any bike (regardless of wheel size), as long as it weighs the same and the surface is smooth will require the same power to climb a hill. The gearing/wheel diameter simply requires a different torque but when the rpm is changed (in order to get up the hill at the same rate) the power will still be equal. (you could simply change the gear ratio to account for the difference in wheel size)

    But two bikes with the same weight/tires/etc. and no power input that are allowed to coast down a smooth hill from a dead stop DON'T get to the bottom at the same time....the one with the smaller wheels will win every time, due to the lesser enertia moment (resistance to acceleration or deceleration) in the wheels.

    Real world....the surface is not smooth...now we must factor in the rolling resistance and moment of enertia (that resistance to changes in speed).

    Now as soon as someone chimes in and starts saying that "a greater moment of enertia is why I like 29ers because once I get it going I can keep it going easier"...well, yeah that is true, but why does that same guy seem to ride light weight aluminum rims and tires....You would get an even larger moment if you increased the weight of the rim and tire with say, lead weights on the rims. anyone doing that? I think we have just embarked on why the advantage is also a disadvantage at times. (hint, I am not talking about the weight penalty of a 29er)

    This is where things get complicated. Suffice to say that 29ers seem to have advantaged in some areas and disadvantages in others.

    A 29er is not an unfair advantage...you may think it is, but I think you will find that the guys who whipped you when you had a 26er will still whip you on your 29er. You may feel better about your own riding though.

    What is it really all about? Engineering the best machine science/money can provide (like Lance Armstrong), or enjoying the ride on whatever we ride? Personally, I like the 29er because it makes me feel like a kid...when I was little the wheels seemed so big.

    Now, I am a big kid.
    Last edited by unit; 02-18-2006 at 05:54 AM. Reason: spelling

  17. #17
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    Finally, a rationale discussion ...

    Quote Originally Posted by dugodugo
    OK...I'll set myself up for this. I rode a Cyclo-cross bike for the first time last fall and it was faster than stink climbing a hill. At first I thought it was the fact that it weighed 18lbs, but I got to thinkin'. Could the 700c wheels have anything to do with it? Everyone says I'm wrong but let me present this.
    Without reason, everyone is wrong.

    Quote Originally Posted by dugodugo
    If you are in the same gears on a 26" and a 29" wheeled bike. Everytime you turn the crank the distance the wheel travels is different. Let's say you are in a gear where 1 crank turn results in 1 turn of the cassette. For every crank turn, a 26" bike will travel (pi x d = 3.14x26") 81.64". However, the 29er will go 91.06" or 10" further with the larger wheels.

    Now the argument I get is that the 29er is not necessarily faster because of the additional effort required due to the larger torque arm of the wheel. In other words, rocks and general frictional resistance create a larger force because they act further out on a 29" wheel (Torque=ForcexDistance). But is it a direct relationship???
    I've heard many, many people site this as a reason for why 29ers are slower. But if you look at the cassettes and chainrings of racers, you'll find that they prefer pushing bigger gear ratios due to their better strength to weight ratios.

    In the end, I think it's a push. There is increased moment of inertia on the wheel. But as you point out, a single revolution of a 29er tire is greater than that of that on a 26er tire. The wheel will indeed take more oomph to get it to go once around, there is a reason for this, your talking about a larger distance.

    Lets look again at the moment of inertia. Yes, it does take fundamentally more energy to turn a larger wheel. But you have have to compare this against the linear inertia of accelerating the frame and more importantly your body weight. What you will find is that accelerating that wheel is INSIGNIFICANT compared to accelerating your body.

    For reference, put your bike (whatever size it is) on a repair stand and shift to the big ring and the smallest cog. Now turn it with your ARM!!!!!! That's right, just your SINGLE relatively weak arm. Than take if off the stand and ride it in the same gearing. This simple example should teach you the profound difference between the inertia in your wheels and the inertia in your body. It's relatively insignificant.

    And lets remember that once you get your slightly heavier wheels moving, they have more energy in them than a 26er. Any spinning object is effectively a "battery" that stores kinetic energy. You will get all that energy back (though it's really not a lot) when coasting.

    My argument is that although the Torque created by "friction" is greater, the rolling resistance is less because the larger diameter rolls over impediments easier. So there is an advantage when it comes to speed.
    I would agree with this statement. Translating forward momentum into bumps tends to dissipate that energy via heat through bouncing the wheels. Many of the same people who diss 29ers will extole the virtues of riding big (and typically thin) rubber that absorbs the shocks and keep you going forward instead of up and down.

    Also a 29'er will weigh a bit more because it has larger wheels and tires. But my sense is you may pick up at most an additional pound.
    Yes, there is extra weight. And if you are a weight weenie, than that it bad no matter what logic is presented. All weight is bad and must be eliminated even it it impinges on the structural integrity of the bike (which will often cause breakdowns and really crappy times). It is a discussion that has NOTHING to do with bigger wheels and more to do with a religious obsession of status. Having the lightest thing makes you better.

    I will point out that even though road racers are amazing weight weenies, there has been no push among them to decrease the size of their wheels. If you use the anti-29er reasoning, road racers would the same motivations to revert to a 26" wheel. Better acceleration and less weight, etc...

    What is often pointed out in this regard is that the road racer has less need for a "strong" wheel than an off-roader. A 26" rim with the same profile will indeed be "stronger" than the same 29" rim. But this analysis often forgets what you pointed out in the first place. The 29" rolls over things better so you're less likely to get tacoed by that rut not from "strength" but simply from the fact that the 29er wont get caught in it like a 26er will.

    All things are a matter of balance. I'm sure a good wheel builder can make a 32 hole 29er wheel just as "strong" as a 26er when you compare them on the basis of who tacoes when running into a 3 ft diameter tree trunk. When it comes to running over roots and logs, the increased angle of attack will negate any advantage of the smaller wheel and will likely save you on your helmet budget. Let's not forget the amount of time saved when you avoid an endo.

    -----------------------------------

    I don't own a 29er, but I hope to one day. The people around my area bad mouth them. They have no personal experience on one. I think that's largely because most people tend to relate more to personal experience than reason.

    I took a 29er out for a test drive at the Fisher dealer and I was impressed. I was rolling over 3" high concrete slabs and they felt like twigs. That was my 280 pound body on 28 whole 29er wheels. I'm not entirely certain that a 28h 26er wheel would have faired so well. My 26er wheels have 36 holes and I'm certain that I need them.

    When I do assemble my 29er, it will have 36 holes on strong rims because I just don't want to fool with it. A slightly heavier wheel with more spokes may not "turn as well". However, a tacoed wheel doesn't turn at all.
    Last edited by willtsmith_nwi; 02-18-2006 at 06:51 AM.

  18. #18

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    Good job! The big Unit got it I think....

    Quote Originally Posted by unit
    Any bike (regardless of wheel size), as long as it weighs the same and the surface is smooth will require the same power to climb a hill. The gearing/wheel diameter simply requires a different torque but when the rpm is changed (in order to get up the hill at the same rate) the power will still be equal. (you could simply change the gear ratio to account for the difference in wheel size)
    Unit....you nailed it I think. Both bikes will require the same power input to get to the top. The factor is who wants it more. Face it, riders do not optimize their power input. The guy cranking up the hill on his 26" HT may only be putting in 90%...while the guy on the 29er feels the resistance of the larger wheels, gets out of the saddle and hammers it at 100%....yea he's gaining 10" on each pedal stroke but he's having to put out the effort. If the course is undulating enough he can recover and keep his gains. However, as you correctly point out, it's all Kinetic Energy....the dude on the Hardtail could get out of the saddle too and selecting the right gear, put out 100% and have a higher RPM, negating the wheel gain of the 29er. Good point....I'm with ya.

    Quote Originally Posted by unit
    But two bikes with the same weight/tires/etc. and no power input that are allowed to coast down a smooth hill from a dead stop DON'T get to the bottom at the same time....the one with the smaller wheels will win every time, due to the lesser enertia moment (resistance to acceleration or deceleration) in the wheels.
    Not sure about this though....you point out resistance moment, but what about reciprocating mass??? I think perhaps that they will get to the bottom at the same time as well, because the reciprocating mass is balanced out by the resistance moment...I could be wrong though.

    Quote Originally Posted by unit
    A 29er is not an unfair advantage...you may think it is, but I think you will find that the guys who whipped you when you had a 26er will still whip you on your 29er. You may feel better about your own riding though.
    Hell...I got whipped by a guy on a single speed the other night and he gave me a 4lb weight advantage on my HT....you've convinced me though that the 29er doesn't have an inherent advantage.

    Quote Originally Posted by unit
    What is it really all about? Engineering the best machine science/money can provide (like Lance Armstrong), or enjoying the ride on whatever we ride? Personally, I like the 29er because it makes me feel like a kid...when I was little the wheels seemed so big.

    Now, I am a big kid.
    Right on dude!!!!!!

  19. #19
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    Like a rolling stone

    Quote Originally Posted by unit

    But two bikes with the same weight/tires/etc. and no power input that are allowed to coast down a smooth hill from a dead stop DON'T get to the bottom at the same time....the one with the smaller wheels will win every time, due to the lesser enertia moment (resistance to acceleration or deceleration) in the wheels.
    By this reasoning, if you put two ball bearings at the top of an incline and release them, the smaller one should reach the bottom first. I don't believe it for a single second.

    Yes the larger bearing will require more torque to reach the same ROTATIONAL velocity. But that rotational velocity will equal a LINEAR velocity that is greater than that of the smaller bearing.

    What about resistance? Lets assume it's optimum, a perfectly flat metal incline. We will assume the balls are also perfect spheres. We will also assume that the surface and the balls do not deform. If you measure the contact distance on both balls, you will find they travel EXACTLY the same distance.

    In the real world, you do have to consider frictional resistance in the surface as well as air resistance in the body. When you figure in an uneven surface (it wouldn't be fun without one) I think you'll find the 29er reaches the bottom first because it travels straighter. Your forward momentum is not redirected into vertical motion and bouncing as much as on a 26er.

  20. #20
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    I find that once the trail points down, my 29" wheels just WANT TO GO. No way that tiny bit of extra weight is resisting the bike to start to roll. Gravity is pulling harder on the wheels too, which evens it out.
    Maybe on a speed record attempt, where you rolls down a snow wall, the greater frontal area of of the 29" tire will keep it from taking advantage of the lower rolling resistant. Maybe.

    Reality : I find myself coasting and even braking my 29"er when riding downhills among 26" bikes that are being pedaled.
    Reality : on flat smooth ground, my non-race 29" tires (don't own any yet, and only the Kenda Karma's exist) just don't roll as well.
    Reality : 26" bikes on the supertires of their choice can't stay with me on winding singletrack. Not even with a fitter, more technical rider aboard.
    Realtity: a 26" bike on my rear wheel will have to lift off for most every corner to not overshoot it, and then close a gap by pedaling harder while I never hit my brakes and never had to spin back up to speed.

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    Emancipation Proclamation

    With apologies to a truly great man, Abraham Lincoln!

    Any 29er discussion that revolves <pun> solely around rolling resistances and rotational inertias misses other major benefits of this layout, like how they fit taller riders. As a tall and particularly long-legged fellow the advantage of a 29er for me is very pronounced. A seat height that gives proper leg extension can be run much more often, as in a vast majority of the time! If some lanky bloke is reading this who's running a compromised lower seat position on a 26" bike just to make it work then he owes it to himself to try a 29er. For me, it was nothing less than freedom from bondage.

    And I think the low gearing "advantage" of a 26" bike is at least partly offset by it having less rear grip and a tendency to spin the tire instead of driving forward.

  22. #22

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    Here is a great explanation of the physics and why a lighter wheel accelerates quicker (ie a larger and therefore heavier 29er wheel suffers compared to a smaller 26er wheel)
    http://www.canecreek.com/168.html

    The moment of inertia of a cylinder or sphere can be written I = umr2, where m is the mass of the object, r is its radius, and u is a number that depends on the shape. larger wheels (greater r and/or greater m) therefore have a larger moment of inertia (all else equal). see http://www.dac.neu.edu/physics/a.cro.../Dynamics.html

    I am not finding any direct examples of a coasting contest between a small diameter wheel and a large, but its not to hard to wrap your head around the concept that inertia is the resistance to changes in acceleration, therefore a lower moment of inertia wheel will accelerate faster...because moment of inertia is proportional to radius squared larger wheels are harder to accelerate. in a coasting wheel the only way to get it moving faster is to acclerate it.

    dugodugo reciprocating mass is not a factor...assuming the wheel is balanced the mass revolves but no mass reciprocates (simple flywheel) heavier flywheel stores more energy...harder to start...harder to stop.

    Reality? yeah this is all pretty real, but as many of you point out, there are so many variables on a trail that these calculations are only a small portion of that reality.

    Who really cares though...go ride, leave the physics for Monday.

    29ers will not file your taxes, or do your laundry, but they are great diversions.

    Sometimes I think we are easily swayed into believing that something that is different is better...ie square taper (never had any problems) replaced by octalink type (is that really any better?) now octalink II (was there some problem that needed fixing?). I now have a BB that requires new bearings each year and it is constantly giving me headaches...funny how my old square taper never gave me problems.

    26ers were fine...now we all switched to something bigger and heavier that also is not as strong (same spoke count on a bigger wheel....) Hey if you like it great...I do. But there is no magic here, it is simply something different that some of us like. Any advantages I pick up here, I pay for there.

    I am not about to come to the 29er forum and attempt to convince anyone here that 29er are not great. They have some strong advantages (the traction for example). But anyone who thinks that these things are superman's cape and there are not disadvantages, is simply too sold on the idea to be objective.

    You like it, you ride it.

    peace

  23. #23
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    It really should come down to how it feels to you! If you give a big wheeled bike a go, and you hate it, then why is there such a big deal, go back to your old bike.. Also, if you ride one and really CANT feel the difference, then congrats, you dont have to buy a new bike!.. Why not have both, thats what I say (although the only mtb I currently have is a 29er). now go ride
    It's not hip hop, it's electro.....

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    yup!!

    Quote Originally Posted by willtsmith_nwi
    By this reasoning,

    SNIP, Yadda yadda yadda


    and bouncing as much as on a 26er.

    You are dead nuts right! I am wrong. Appologies.

    In a coasting contest the larger wheel will likely win...especially on a real surface we might expect to find in nature.

    However, I am sticking to my guns the other statements. Especially those regarding 29ers being great, but not magic, or clearly superior in all cases. I ride mine in pretty much all cases, but in some (such as those involving need for wheel strength) I realize I have a disadvantage and ride accordingly.

    Sorry to blunder.

    Ken

  25. #25
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    Quote Originally Posted by unit
    I am not finding any direct examples of a coasting contest between a small diameter wheel and a large, but its not to hard to wrap your head around the concept that inertia is the resistance to changes in acceleration, therefore a lower moment of inertia wheel will accelerate faster...because moment of inertia is proportional to radius squared larger wheels are harder to accelerate. in a coasting wheel the only way to get it moving faster is to acclerate it.
    Moment of inertia is proportional to radius squared - very true, BUT, when you are doing the calculations for a accelerating vehicle, the wheel radius terms drop out. The radius of the wheel has nothing to do with accelerating it via rolling, beyond the simple fact that a bigger wheel of similar construction will be heavier. Weight is the only thing that ends up mattering.

    So yes, 29 inch wheels, assuming they are heavier, will accelerate slower than 26" wheels. But a light cyclocross tire, even though bigger in radius, will accelerate faster than a smaller, heavier wheel.

    As for having 10% more distance to roll with the same "gear ratio" - it's not the same thing. Think about how gears work. A low gear makes you move a small distance per pedal revolution, a high gear you move a bigger one. Whether you get that extra distance by using a bigger chainring, a smaller cog, or a bigger wheel, it's all part of the same chain of levers that make up your drivetrain. See the esteemable Sheldon Brown's gain ration page:

    http://www.sheldonbrown.com/gain.html

  26. #26
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    All wheels are the same

    Quote Originally Posted by unit
    I am not finding any direct examples of a coasting contest between a small diameter wheel and a large, but its not to hard to wrap your head around the concept that inertia is the resistance to changes in acceleration, therefore a lower moment of inertia wheel will accelerate faster...because moment of inertia is proportional to radius squared larger wheels are harder to accelerate. in a coasting wheel the only way to get it moving faster is to acclerate it.
    That's because there isn't any difference between coasting of a big or a small wheel. Look at the page you cited - example 3. The velocity of a wheel (hollow cylinder) is given by

    V(squared) = 2 g h / ( u + 1 )

    for a cylinder u = 1 so the equation simplies to V = g h the only things that matter are gravity and the height of the ramp.

  27. #27
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    personally, I dont think 29" is any advantage over 26" than just speed. mostly because I destroy a lot of rims. the bigger the rim, the more weak it is (depending on the rim) my BMX (20") has seen a LOT of abuse, includeing falling down 12 feet to concrete in the skatepark. the rims, are just fine. then my P.1 runs a 24" in the back, its been fine so far (but not too many crazy accidents) but the 26" rims in the front, i've gone through 3 of them. so basically...how I ride....a 29er would get so trashed.
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  28. #28
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    Rotational != Linear

    Quote Originally Posted by unit
    Here is a great explanation of the physics and why a lighter wheel accelerates quicker (ie a larger and therefore heavier 29er wheel suffers compared to a smaller 26er wheel)
    http://www.canecreek.com/168.html

    ...
    but its not to hard to wrap your head around the concept that inertia is the resistance to changes in acceleration, therefore a lower moment of inertia wheel will accelerate faster...because moment of inertia is proportional to radius squared larger wheels are harder to accelerate. in a coasting wheel the only way to get it moving faster is to acclerate it.
    ...

    peace
    Yes, a smaller wheel will accelerate faster ROTATIONALLY. LINEARLY, each rotation of a larger wheel gets you farther. If you do the math, you'll find out that the faster rotational acceleration of the smaller circumference vs the slower acceleration of the larger cirmuference are exactly the same. For the same amount of energy applied to the same mass, the two vehicles will accelerate the SAME linearly. The weight of the wheels do not matter beyond getting the gearing tuned for the engine (you).

    Try the experiment I suggested earlier with cranking with your hands in the highest gear ratio, you'll realize how ridiculous this whole discussion is.


    BTW, I read that Cane Creek page. I really like what Cane Creek does, however they've put some misleading information in the document. They've implied that the difference between their spoke nipples and other is a factor of 180. They fail to constrain their argument to the masses and energies they are talking about and express it in terms of the overall moment of inertia of the wheel.

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    granted...

    Quote Originally Posted by willtsmith_nwi
    Yes, a smaller wheel will accelerate faster ROTATIONALLY. LINEARLY,...

    you'll realize how ridiculous this whole discussion is ridiculous.

    ....

    Yes, I guess it is quite ridiculous at this point....if you go up thread and see that I FLAT OUT SAID I was wrong and YOU were spot on (1:13 PM)...you jumped up and restated that I was wrong at 3:58! I guess you are also not perfect.

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    Nothing personal, just physics ..

    Quote Originally Posted by unit
    Yes, I guess it is quite ridiculous at this point....if you go up thread and see that I FLAT OUT SAID I was wrong and YOU were spot on (1:13 PM)...you jumped up and restated that I was wrong at 3:58! I guess you are also not perfect.
    I am not right, Isaac Newton is. Nothing personal. And I apologize if it seems I am piling on. I didn't mean it that way.

    I'm taking math proofs right now in my second academic career. Every time I give my professor work, he rips me a new one. He told us up front he would, it's nothing personal. It's the idea that is being attacked, not the person.

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    Good job! It's all good...

    Hey guys...I started this little(?) thread not to start flames, but to just raise some ideas. We all have ideas and I'm not sure any of us are in a position to state without a doubt what's what....the point has been made, and rightfully so, that there are just too many variables and too much uncertainty to really know for sure what is going on.

    My analytical side says that the physics works out that regardless of wheel size both bikes require the same amount of work/power to reach the top of an incline. I guess I'm sold that larger wheels have no mechanical advantage other than rolling a little smoother.

    However, as some one stated a while back, side by side comparisons of a 26er and 29er seemed to indicate that the 29er was faster. Did it just make you work harder and therefore you went faster. That's my point. As I stated the power output of humans is not consistant and that's what makes it so hard to figure out what's going on. Maybe it is that the larger wheels draws more output from you and you go faster because your working harder. I don't know.

    My experience with my crossbike is that I get a better work out from it than just crianking up an incline on my 26er because I hammer it out of the saddle more. It's like that guy I told ya kicked my butt on a single speed....I've seen this effect before. A single speeder actual has less mechanical advantage and therefore works harder and seems to go faster. What's up with that????

    I guess it's the "X Factor".....

  32. #32
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    gyro effect

    I've noticed an increased gyroscopic effect in my 29er over my 26," as well as over my road/cyclo stuff. My hunch is that this increases straight line efficiency and recovery from side forces (bouncing around rocks, etc.) with less momentum loss, even as it seems to inhibit flickability at speed or throwing the bike from side to side when hammering. It should not hurt carving however. I would guess that wheelbase more than wheel size would effect quick moves. Anyone care to comment on this advantage/disadvantage of the 2 sizes and having more weight further out?

  33. #33
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    Read the FAQ, and then come back here to attack each of the claimed advantages. There's much more than just smoothness.If you can't notice any more, you need to ride the 29"er harder :-)

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    on to psychology

    Quote Originally Posted by dugodugo
    Hey guys...

    My analytical side says that the physics works out ...

    However, as some one stated a while back, side by side comparisons ....

    My experience with my crossbike is .....What's up with that????
    after failing the physical demonstration...I will move onto Psych. 101

    Seriously, thinner tires on a CX bike will tend to fly in certain circumstances. I think thinner tires on a 26 would do the same.

    As for the psychology...I ride SS all the time...on a 29er. It feels right to me, but not necessarily faster. there are advantages, but knowing that that dude ahead of me on the trail has a CX bike with gears (like happened on Friday) makes me pound my heart out to catch him. When I did (because he stopped and waited) I had the choice to make...was it me (the engine) was it the bike (the 29er) or was it the fact that he stopped and waited?

    I will choose A and C. I dont think I am faster because it is a 29er under me....I think I am faster because I like riding it...and I ride it more BECAUSE I like it....and that makes me faster (i.e. if you ride more and ride harder, you will get stronger/faster).

    Seriously, ride what you like. 29ers are great, but again they are not magic. If you try one in you conditions you will see if the advantages play out....I would bet that you like the advantages so much that you dont notice any disadvantages....but they do exist, so remember that there are limitations and ride accordingly...then you WILL be faster.

    NOW, go out and ride.

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    second HHL

    I think HHL has the most objective observations on this thread so far. If you think there are no disadvantages whatsoever to 29, you are crazy, or you ride trails that are a lot different than the ones I ride. I think the lab physics discussions are interesting, but are not as noticeable as some more basic empirical observations that I buy into i.e.:
    29 disadvantages:
    1) more weight, more flex in the wheels, frame and fork makes it harder to accelerate/ wind up after stalling out, particularly on a technical climb
    2) increased wheelbase makes it harder to wheelie, harder on switchbacks, most places where "flickability" is needed
    3) Either tire choices or contact patch shape makes for more rolling resistance. 29 also has more traction, so I tend to think it is more contact patch shape on both counts. I would theorize that the longer 29er patch may demand more flex from the tire?

    Advantages I buy into:
    1) More momentum and gyroscopic stability, particularly downhill
    2) More traction
    3) Smoother ride, making it more feasible/comfortable to ride hardtail/rigid on rougher stuff
    4) Better fit for taller riders
    5) Increased abililty/ speed on faster carving-type turns. Due to increased BB drop?

    I bought into 29ers October '04 with the purchase of a 293. Since then I have also owned a Buzzbomb and a Leviathan. I have recently gone back to the "dark side" and purchased a 26" SC Blur LT. I'm never gonna sell the Sugar, because I love it, it is fun, it is better at a few things, it is great for beginners, and mostly because it is different. But I am not riding it much right now, mostly because it simply is not as good at the type of riding I like to do most.

    I think that 29ers are better for 80% of the people who ride hardtails, 90% of those who ride rigid and/or singlespeed, but more like 50% of those who prefer FS. Depends heavily on local terrain, obstacles, and skill level/ body style of the rider.

  36. #36
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    Quote Originally Posted by heavyg
    3) Either tire choices or contact patch shape makes for more rolling resistance. 29 also has more traction, so I tend to think it is more contact patch shape on both counts. I would theorize that the longer 29er patch may demand more flex from the tire?
    Nope. Larger wheels have less rolling resistance. See "Bicycling Science" by Whitt and Wilson, pp124-126 in the second edition.

    Larger wheels also flex less in the sidewalls. Look for papers published by Chester R. Kyle on this subject. I have photocopies but they don't list what journal they were published in.


    Quote Originally Posted by heavyg
    Advantages I buy into:
    5) Increased abililty/ speed on faster carving-type turns. Due to increased BB drop?
    But BB height and therefore center of gravity will be the same. The increased drop is only a function of frame design around the taller wheel.

  37. #37
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    Quote Originally Posted by heavyg
    29 disadvantages:
    1) more weight, more flex in the wheels, frame and fork makes it harder to accelerate/ wind up after stalling out, particularly on a technical climb
    2) increased wheelbase makes it harder to wheelie, harder on switchbacks, most places where "flickability" is needed
    3) Either tire choices or contact patch shape makes for more rolling resistance. 29 also has more traction, so I tend to think it is more contact patch shape on both counts. I would theorize that the longer 29er patch may demand more flex from the tire?

    Advantages I buy into:
    1) More momentum and gyroscopic stability, particularly downhill
    2) More traction
    3) Smoother ride, making it more feasible/comfortable to ride hardtail/rigid on rougher stuff
    4) Better fit for taller riders
    5) Increased abililty/ speed on faster carving-type turns. Due to increased BB drop?
    Re : Disadvantages
    1) More weight, okay, but if you add a mere 20g/wheel (4 spokes extra) you get rid of the wheel flex factor already. It's not like any26" wheel will be stiffer than any 29" one. Also, any flex issues are mainly due to the lacking flange spacing. Larger wheels ask for wider spacing.
    2) What extra wheel base? The XL 26"bike I recently sold had 1/2 more wheelbase than my current XL 29"proto of the same size. The 29" bike even has more top tube length.
    3) The idea with larger diameter tires it tht they need to comply under such a large angle. less resistance. The longer but narrower contact patch focusses the pressure on the knobs where you want it. Maybe this means that a continious center tread is more important for 29" to roll well? (I just came up with this)

    Re : Advantages
    Traction yes, but especially cornering grip. Cornering is soooo much easier now, and fast too as I notice how much easier it is too keep up with top level 26"riders in twisty stuff,a nd how they fail to keep my rear wheel through it, even when my fitness is lacking.
    Much less need to get on the pedals after a turn as you maintained more speed through it, more than compensating for increased wheel weight.
    Klok - XC - Skate - Ski

  38. #38
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    All in all, the 29er makes perfect sense to me after all Ive read on the subject. A couple pound weight gain really aint squat, even if alot of it is in the wheels (which is way over rated anyhow; wish more folks would be as in tune and on subject with rolling resistance which is way more critical). I find that goin over and through stuff seems to my biggest challenge on most of the stuff that I ride so it was a no brainer for me to go 29 for a new ride. Bye the way, thanks to all you guys who have already done all the research and experimenting and what not. Makes it nice for rest of us bums to just open our wallets!

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    Under a pound penalty, actually.

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    Calling all Brainiacs

    OK, I've been waiting to pose this question for some time now. Math and physics are not my forte, but it seems we have some guys on this thread who know their way around an equation. Has anyone read (in detail) the article that is quoted on the Bontrager website regarding 26 vs 29 wheels and the study done by Pepperdine University involving an uphill time trial and crosscountry comparisons? The article (I'm assuming it is actually an abstract of an article) concludes that the 29er was faster by 4% on the uphill time trial and 3% faster on a cross country lap than the 26er. My background is in science but not the physical sciences (I'm a root canal specialist), so I have some experience in critically evaluating literature. I see right off that there is a problem with sample size (6 riders) but what do you brainiacs make of this study other than it wasn't a large group studied. http://www.bontrager.com/Workshop/Te...nch_Wheels.php

  41. #41
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    Quote Originally Posted by tibiker325
    OK, I've been waiting to pose this question for some time now. ... what do you brainiacs make of this study other than it wasn't a large group studied. http://www.bontrager.com/Workshop/Te...nch_Wheels.php
    I'll have to dig up the full paper to see what their methodology was, but looking at their conclusion:

    We attribute the faster course completion times on the 29” vs. 26” bicycle to the larger wheel traveling a greater distance per pedal revolution (average power outputs were not different between bicycles), and likely to a cumulative effect of the larger wheels rolling faster and more easily over obstacles during the uphill and cross-country trials.
    If they can't separate the "greater distance per pedal revolution" from overall gear ratio (including the wheel size), I think they don't understand what's going on. That doesn't mean that 29'ers aren't faster - their measurements may be accurate and 29'ers might actually be a few percent faster, but it's not due to circumference.

    There was another study around '94 or '95 that tested hardtail versus full suspension. They used a inclined treadmill with pieces of wood bolted to it to simulate bumps. I believe that they found the FS bikes to be either faster or more energy efficient, despite the greater weight. I think it was done at Texas A&M, and I'm almost positive it was published in the journal Cycling Science.

    So if FS is measureably faster in lab conditions, it doesn't shock me that 29'ers would also test similarly. Like suspension, they help mitigate the losses you encounter due to bumps and the like. Which leads me to point out one thing - when suspension came out, a lot of the arguments against it were weight and flex. But it seems the tradeoffs are worth it since just about every bike these days has front suspension. Aren't 29 inch wheels just another place where you trade off a little bit of weight for a bit more control and speed?

  42. #42
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    Gotta love people that proudly put their name on a paper when really they haven't started to see any of the factors at work.

  43. #43
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    Quote Originally Posted by dr.welby
    If they can't separate the "greater distance per pedal revolution" from overall gear ratio (including the wheel size), I think they don't understand what's going on. That doesn't mean that 29'ers aren't faster - their measurements may be accurate and 29'ers might actually be a few percent faster, but it's not due to circumference.
    Their abstract says it differently, so whose conclusion was it? An editor at Bontrager?



    THE EFFECTS OF MOUNTAIN BIKE WHEEL SIZE ON PERFORMANCE IN UPHILL AND CROSS-COUNTRY CYCLING.

    J.T. Herr and H.S-H. MacRae. Dept. of Sports Medicine, ffice:smarttags" /><ST1lace><?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-comlace>, <ST1lace><st1:City>Malibu</st1:City>, <st1:State>CA</st1:State> <st1:PostalCode>90263</st1:PostalCode></ST1lace>.

    Purpose: Since mountain bike cycling performance is affected by bicycle design, the purpose of this study was to assess the effect of wheel circumference on mountain bike performance during uphill (UP) and cross-country (XC) cycling. Methods: Five sub-elite cyclists (34 ( 1.9 yr, 63.5 ( 6.3 ml.kg-1.min-1, 6.14 ( 0.5 W.kg-1 peak power) completed an UP course (1.38 km, 123 m elevation gain) and XC loop course (3.63 km, 158 m elevation gain) on mountain bikes equipped with either standard 26” (STA) or big 29” (BIG) circumference wheels. During these field trials, expired gases were continuously measured with a portable metabolic system (VO2000, Medical Graphics), and cycling performance (as measured by time to complete the courses (T), power output (P), cadence (C), speed (S), and heart rate (HR)), with an SRM Training System. Results: The gas exchange data are not reported here. Mean HR’s were not different between STA and BIG during UP (170 ( 9.4 vs. 172 ( 5.9 bpm), or during XC (168 ( 7.9 vs. 168 ( 8.5 bpm). Mean HR’s during UP were ~ 94% HRmax, and ~ 93% HRmax during XC. The time to complete the UP course was faster on the BIG wheel bicycle (6.33 ( 0.3 vs. 6.68 ( 0.4 min on STA, p = 0.03), and the XC course completion time was also faster on the BIG equipped bicycle (13.62 ( 0.5 vs. 14.0 ( 0.4 min on STA, p = 0.02). Absolute P (uncorrected for bicycle mass) was not different during the UP trials between STA and BIG (average P was 267 ( 45 vs. 300 ( 47 W), or during XC (average P was 200 ( 50 vs. 207 ( 56 W). Conclusion: Larger circumference wheels improve mountain bike performance during climbing and cross-country riding, with no detrimental effect on cardiovascular (HR) or muscle (P) function.

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    Quote Originally Posted by edoz
    Ha! Somebody's sig here says people who don't understand 29ers are the people who take a Ford Ranger to a monster truck rally. Something like that anyway.
    HAHAHA. That is mine! It is my simple minded way of explaining 29'ers to my friends here in the Southeast. HAHA, the only other way to get it across to the people here is to say Jesus rode a 29'er (Just kidding)

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    My pants say yes!!!

    Quote Originally Posted by Maxrep
    This is just a re-post from several weeks ago. It may add some perspective to the pro / con issues :

    The crux of the con:

    As a magician draws you into his performance, there is a purposeful distraction that your attention is drawn to. This alternate display effectively shifts your focus to a benign activity while the crux of the trick goes unnoticed.

    I too was distracted in comparing 26 inch and 29 inch wheels. Mental hurdles I could not get past were two fold. The extra rotating weight further from the hub(gasp ) and wondering how I could wrestle that "screaming war pig" through the single track.

    Though these two items seemed insurmountable, they turned out to be nothing more than smoke and mirrors against the real issue. A riding buddy who's opinion I valued, had a 29er and liked it. I gave it a try.

    I thought I would give up a little speed in the woods, but gain more time on the double track or roads. To my surprise, I found myself riding faster through the single track with out any pig wrestling issues at all. More confidence in the turns, less skiddering in the corners, better traction, and the rock gardens were effectively smoothed out.

    The real issue never lay with the 29er. The crux of the problem falls to the 26 inch bike! It is slower on the flats, but the fatal blow takes place in the woods, which is where we all thought its best hand would be played. The problem never was re-accellerating the 29 inch wheel - the problem is that every turn causes the 26 inch rider to shave extra speed entering and exiting. Not only then does the 26er have to re-accellerate its wheels more, the entire bike and rider(much more substantial) have to be brought back up to speed after each turn too. The yo-yo effect.

    The most important part of biking is enjoying the activity, regardless of bike or budget. That said, 2 months ago the group of mostly pro/elite riders I ride with had one 29er amongst us. There are now 6. Between us, there are a few years of experience and a fair amount of trail familiarity. I would say this is collective agreement that the 29er is the better option rather than a demonstration of the latest fad.

    Chances are that if you ride with someone who has a 29er, your next bike purchase is likely to be a 29er.
    Wow...this spells it out for me. I was given the plesure of riding Tim's (SSweetLeaf....thanks ton's dude)) this past weekend. I could feel the extra effort required to accelerate the bike, but once up to speed it seemed a lot more effortless to keep the momentum going. It just floated along and rolled over the rough stuff. I got to run it on a packed section of a two track out of the saddle and it just seemed to keep picking up speed. Seat of the pants tells me that 29er's are faster and probably along the lines of the studies done above. I didn't get to ride it in any real tight stuff so not sure of handling. But it was sweet, no doubt.

    Which brings me to my original question...why does NORBA allow them to compete head to head with 26er's and why haven't more 29ers won major races???

  46. #46
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    All I know is that using a 29r for a full rigid seems to work out better than using a 26" for most riding.
    The trail is definitely "smoothed out", even going up/down curbs is easier.
    A more aggressive ride style via a 29r's corning potenial is increased because of increased contact patch too.
    I think the whole gearing issue is another story, as that sort of might lend itself to more complex solutions to equal a 26" -> 29r.
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    Racing should improve the breed...

    Quote Originally Posted by Maxrep
    The race exposure among the pros is directly related to the sponsored ride. Who besides fisher sponsors a 29er? Well, here in MI we have the Quirring/Bells beer 29er team, but that is a local example.

    A buddy of mine and myself race pro/elite. We both have done better on the 29ers than the 26 inch bikes. Of course that is quite anecdotal, but it works for me!!!
    So you're telling me Specialized has to get it's ass handed to it by Fisher before they adopt a 29er??? Uhmmm....something there ain't right. If 29er's are faster which I believe we're starting to get a concensus on, then what's up with the race teams??? I'm not sure of the rules but I thought it was pretty much "run what ya brung" at least in NORBA. Is World Cup different??? Do they limit 29er's??? And if not, why haven't more race teams jumped on this advantage???

    That's what has me going!!!!

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    Most racers, even those over 6'5", just don't give a damn, or think they already have the pinnacle in cycling kicking them in the behind. There's 2 kinds of people in cycling : farmers and intellectuals. Most put themselves in the latter category. In the grand scheme of things, most will actually be in the former. It gets exciting when farmers start to do engineering/design/analysis, it can go either way, pure genious or complete stupidity.

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    Farmers we are....

    Quote Originally Posted by Cloxxki
    Most racers, even those over 6'5", just don't give a damn, or think they already have the pinnacle in cycling kicking them in the behind. There's 2 kinds of people in cycling : farmers and intellectuals. Most put themselves in the latter category. In the grand scheme of things, most will actually be in the former. It gets exciting when farmers start to do engineering/design/analysis, it can go either way, pure genious or complete stupidity.

    Cloxxki....you crack me up dude....too funny.

  50. #50
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    Quote Originally Posted by willtsmith_nwi
    Yes, a smaller wheel will accelerate faster ROTATIONALLY. LINEARLY, each rotation of a larger wheel gets you farther. If you do the math, you'll find out that the faster rotational acceleration of the smaller circumference vs the slower acceleration of the larger cirmuference are exactly the same. For the same amount of energy applied to the same mass, the two vehicles will accelerate the SAME linearly. The weight of the wheels do not matter beyond getting the gearing tuned for the engine (you).

    Try the experiment I suggested earlier with cranking with your hands in the highest gear ratio, you'll realize how ridiculous this whole discussion is.


    BTW, I read that Cane Creek page. I really like what Cane Creek does, however they've put some misleading information in the document. They've implied that the difference between their spoke nipples and other is a factor of 180. They fail to constrain their argument to the masses and energies they are talking about and express it in terms of the overall moment of inertia of the wheel.
    The difference is unperceivable! Now, cleaning the next section cuz you got big wheels thats da perceivable. Dont buy into wheel weight hype. The manufacturers are brain washing us. The narrowest, fastest rolling tire set up that gives you the optimum performance is %%%%% more of an issue.

  51. #51
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    Not for me...

    Quote Originally Posted by dugodugo

    So let the discussion begin. Do 29ers have an inherent advantage over a 26" bike based on the Wheel size?
    I've looked down this thread - great discussion and more or less civil. Impressive

    The Pepperdine abstract posted on the GF site comes from an unpublished study. We have no idea about the size of the riders, the type of terrain etc. No way could any sort of conclusion be drawn from that.

    Last summer I was smitten with the 29er bug and got a 292, then shortly thereafter a Dos Niner. As soon as I got the 292, my Fuel went unused for months...I was an immediate convert. As fun as the bike is, I slowly came to think it might not be as *fast* as I thought it was. To answer this question, I purchased a power tap hub for the 29er (already had one for the 26er) and did a few studies.

    This thread talks about all the physical factors I can think of like rolling resistance, moment of intertia, traction, etc. It stands to reason the bigger wheels would be better in some areas and not so good in others - but rather than doing "thought experiments", how about the real thing?

    Here are some links to the tests I've done. Take it for what it's worth. I have no financial stake in one wheel size or another, I'm just a guy who wants the fastest rig I can get. It might be beneficial to keep in mind that I'm 5' 8.5" and 145# - not a big guy like many who really enjoy 29ers.

    On climbing: http://teamhealthfx.com/blogs/dave_h...01/02/309.aspx
    On singletrack: http://teamhealthfx.com/blogs/dave_h...02/10/510.aspx
    On racing: http://teamhealthfx.com/blogs/dave_h...02/21/571.aspx

    I'm not trying to convince anyone of anything - these are simply my experiences.
    Dave

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    Ya know what really got my attention to consider a 29er? Average size folks with alot of experience were selling or had sold off all their 26" bikes. Thats pretty convincing! Cuz I love my bikes and Ide have to be really convinced that they were relics to even think of parting with them and these guys are far more passionate thaan I.

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    Good job! Wow...this is more than real world!!!

    Quote Originally Posted by hairball_dh
    I've looked down this thread - great discussion and more or less civil. Impressive
    Dave....you are an impressive individual. My hat's off to you for being able to duke it out with Tinker in a 24Hr. contest. too bad about the eyes...Hope your eyesite has returned to normal. It sounds like there'll be other races....

    I was inpressed with your analysis....you did what I believe is the crux of this whole issue. You used a Power Tap to normalize the power input and come up with a side by side comparison....going through your analysis it seems you have determined that the 26er is better for your riding than the 29er, given its manuverability.

    What situations would you think the 29er had advantages over the 26er???

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    @hairball_dh :

    With differences so minute (obviosuly almost), how did you measure and set rear tire circumference for both setups? Especially in a climb (rear tire "working") I can see how results could be slightly distorded, as all PT data seems based on tire size?

    Great testing, superb work! I'd love to see it done with even more identical tires though, like Nano 26x2.1 vs 29x2.1. Tire that not only are the same width and quality on paper, but also in reality.

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    [QUOTE=

    What situations would you think the 29er had advantages over the 26er???[/QUOTE]


    Mt. biking of course. That was easy. Next question.

    Dont get me wrong. I think the test was a good test and shows when a 29 might not be a good choice. Reminds me of the rigid/suspension and then the suspension/fully wars. Weird how history repeats itself. Personally I have decided to go to a 29er for the same reason I went susp and then full susp and that needs no explanation at this point. If I was riding the terrain that is explained in the test, I would not even fathom dropping the coin on a 9er. Nor would I even look into it. Sounds like a good no susp hardtail might be the nuts for the terrain that was ridden in the test.
    Last edited by Fisty; 02-22-2006 at 03:58 PM.

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    Thanks for the kind words

    Quote Originally Posted by dugodugo
    Dave....you are an impressive individual. My hat's off to you for being able to duke it out with Tinker in a 24Hr. contest. too bad about the eyes...Hope your eyesite has returned to normal. It sounds like there'll be other races....

    I was inpressed with your analysis....you did what I believe is the crux of this whole issue. You used a Power Tap to normalize the power input and come up with a side by side comparison....going through your analysis it seems you have determined that the 26er is better for your riding than the 29er, given its manuverability.

    What situations would you think the 29er had advantages over the 26er???
    Now, as for where the 29er might be best...I haven't stumbled into it yet, but that might have something to do with my size. I'm not a big guy..

    I'd guess that rocky, rooty terrain with short climbs (<30 seconds) and not too tight of turn might be the best place for a 29er. Also I can envision the 29er being advantageous for SS use. 29ers feel awesome on descents, especially my 292 (that I've sold). Of course, those are just guesses.

    When switching between bikes, the smaller wheeled bike was more manuverable for me, but also accelerated faster.
    Dave

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    Quote Originally Posted by Cloxxki
    @hairball_dh :

    With differences so minute (obviosuly almost), how did you measure and set rear tire circumference for both setups? Especially in a climb (rear tire "working") I can see how results could be slightly distorded, as all PT data seems based on tire size?

    Great testing, superb work! I'd love to see it done with even more identical tires though, like Nano 26x2.1 vs 29x2.1. Tire that not only are the same width and quality on paper, but also in reality.
    The PT calculates power using angular velocity, not linear velocity, so circumference isn't a factor. The first test (climbing) was later done with identical tires and the Fuel just got faster - it turns out the Specialized Fast Traks have become a new favorite of mine as a result of the testing.

    The recent test of the OP race was done with Fast Traks all the way around. I've done everything I can think of to speed up the 29er, it just seems to lag behind a bit. Kinda painful, because they are so darn fun to ride.

    If I didn't race, I'd still be riding that 292. That bike gave me new enthusiasm for cycling...
    Dave

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    guess I will play devil's advocate

    we brought up the power meter as a deciding tool for 26 vs. 29 last week. The results seem to be in....

    BUT

    The real test is not necessarily the power/work done at the crank or rear wheel for that matter....If it was, then everyone in the world would simply reduce machine weight (ie eliminate all forms of heavy suspension) since that would maximize the use of the available power.

    the real test is stress on the human body....very hard to quantify (perhaps a reason this discussion goes on and on and on). Modern formulae for quantifying this are based in power from legs...but that is not the whole story.

    The stress on the body is not simply power production at the crank or rear wheel, but also the fatigue from shock encountered resulting from bumps, roots, etc., lifting the front end over obstacles etc..

    As has been stated in the past...there are perceived advantages and disadvantages to both 26 and 29. I fear that a clear cut winner will never emerge.

    Dave have you compared estimated threshold powers (One hour critical power, or some other duration) on both machines? not sure how else you would hope to quantify the difference in stress on the body? any ideas? But as you point out the terraine is probably a major factor. I guess its a moot point though...looks like you have made *your* decision/solution to this unique problem.

    Ken

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    A good read and maybe a variable to consider when testing

    I realize this refers to road bike but physics are applicable.
    http://www.fitwerx.com/NewFiles/Tech...esistance.html

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    Quote Originally Posted by unit
    we brought up the power meter as a deciding tool for 26 vs. 29 last week. The results seem to be in....

    BUT

    The real test is not necessarily the power/work done at the crank or rear wheel for that matter....If it was, then everyone in the world would simply reduce machine weight (ie eliminate all forms of heavy suspension) since that would maximize the use of the available power.

    the real test is stress on the human body....very hard to quantify (perhaps a reason this discussion goes on and on and on). Modern formulae for quantifying this are based in power from legs...but that is not the whole story.

    The stress on the body is not simply power production at the crank or rear wheel, but also the fatigue from shock encountered resulting from bumps, roots, etc., lifting the front end over obstacles etc..

    As has been stated in the past...there are perceived advantages and disadvantages to both 26 and 29. I fear that a clear cut winner will never emerge.

    Dave have you compared estimated threshold powers (One hour critical power, or some other duration) on both machines? not sure how else you would hope to quantify the difference in stress on the body? any ideas? But as you point out the terraine is probably a major factor. I guess its a moot point though...looks like you have made *your* decision/solution to this unique problem.

    Ken
    Threshold power in this application is really determined by bike fit - which in this case is close to identical. PTs as a strain guage based device have inherent inaccuracies that are measureable via a "stomp test". I've tested them both so as to control for the inaccuracies, and as a double-check, high intensity tests come out within a couple watts on each machine.

    You are absolutely right that a clear cut winner will never be determined. Given the infinite variety/combination of body type/size, terrain, riding style, bike setup...the permutations are endless. I just had to find out for myself what was going to be best cause I take my racing a wee bit seriously I am now getting a feel for what is best for me...and hopefully by sharing the results it at least provides some food for thought.

    The fatigue issue - that's a biggie in 24s. The Fuel is hands down easier on the body than the Dos. The 292 was easier on the bod than either at Moab last year, and I rode the 292 for at least 3/4 of the laps - I had all 3 at my disposal.

    Riding fast is not everyone's goal - and this is an important point. I had more fun riding that 292 last summer than any bike in recent years. It just wasn't that fast when climbs came into the picture.
    Dave

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    great bliing for FoShizzle

    Quote Originally Posted by dugodugo
    Dave....you are an impressive individual. My hat's off to you for being able to duke it out with Tinker in a 24Hr. contest. too bad about the eyes...Hope your eyesite has returned to normal. It sounds like there'll be other races....

    I was inpressed with your analysis....you did what I believe is the crux of this whole issue. You used a Power Tap to normalize the power input and come up with a side by side comparison....going through your analysis it seems you have determined that the 26er is better for your riding than the 29er, given its manuverability.

    What situations would you think the 29er had advantages over the 26er???
    Fascinating but unconvincing.

    (1) In trying to understand the claims for accuracy I looked at the "stomp test". Dave used a 30 lb weight, but on the web I found this --

    Now, measure torque as follows: with the cranks exactly horizontal (right crank at 3 o’clock), hang a known weight of at least 50 lbs from the right crank, or simply stand on it – hence the name ‘stomp test’! Measured torque = (weight in lbs) × (crank length in mm) × (1 in/25.4 mm) × (cog teeth/chainring teeth). For a 159 lb rider standing on a 175 mm crank, with the chain on the 39 tooth ring and the 23 tooth cog, 159 lbs × 175 mm × 1 in/25.4 mm × 23/39 = 646 in-lbs. Compare this to the displayed value by calculating % error as (measured torque - displayed torque)/measured torque.
    <O</O<O</O
    <OThe calibration torque is just too low for both bikes. The example is nearly 3 times Dave's calibration point. To represent real conditions the 29er should be calibrated at a torque 10% higher than the 26.</O
    <O</O
    <O(2) Dave's percent calculations are off (time must be redone) but the inaccuracy makes the point moot, the Power Tap only claims +/- 1.5% accuracy (same source)</O
    Last edited by pacman; 02-22-2006 at 02:13 PM. Reason: noise

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    Hey Dave

    Looking at the histograms (guessing these came from cycling peaks?) The data is pretty....well all over the place. Have any histograms that sample a greater volume of data? would love to see a couple weeks worth of data plotted in this manner for each bike (might be able to get some insight as to an estimate of threshold power)

    The lap times would seem to indicate what bike is truely faster, but can we eliminate other factors? While your time on the 29 is longer (time duration) your Power is lower too. 5 watts lower (avg and normalized) over roughly 10 minutes....do you attribute that to the bike? Your position? Your (dis)comfort on the 29? Better rested for one run vs. the other?

    Thanks for the interresting turn in the conversation.

    While many MTB power guys report a lower threshold power (TH) on MTBs (compared to road) due to the added stress on the upper body...I wonder if from your data sets we might see if one bike reduces the TH more than the other (indicating perhaps more stress on the upper body causing a reduction of energy (glycogen stores) available for the legs).

    any thoughts?

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    yeah....to part of Pacman's point I believe, the real advantage to 29er is that, generally speaking, the stuff is bigger. In addition to frames being a bit bigger on the average, in concert with In addition, the wheels are bigger so when you go with something like colored spokes on say an Industry Nine wheelset, the 29er wheels and larger frame will provide more room for bling. Other than that, no real difference.

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    Lots of thoughts...

    Quote Originally Posted by unit
    Looking at the histograms (guessing these came from cycling peaks?) The data is pretty....well all over the place. Have any histograms that sample a greater volume of data? would love to see a couple weeks worth of data plotted in this manner for each bike (might be able to get some insight as to an estimate of threshold power)

    The lap times would seem to indicate what bike is truely faster, but can we eliminate other factors? While your time on the 29 is longer (time duration) your Power is lower too. 5 watts lower (avg and normalized) over roughly 10 minutes....do you attribute that to the bike? Your position? Your (dis)comfort on the 29? Better rested for one run vs. the other?

    Thanks for the interresting turn in the conversation.

    While many MTB power guys report a lower threshold power (TH) on MTBs (compared to road) due to the added stress on the upper body...I wonder if from your data sets we might see if one bike reduces the TH more than the other (indicating perhaps more stress on the upper body causing a reduction of energy (glycogen stores) available for the legs).

    any thoughts?
    ...but they all lead down roads that aren't good subject matter on this board. Hit me on my blog if you'd like to pursue this further. It's all about training with power - and I've got about as much experience as anyone with power on an MTB. It will get a lot of yawns here though.
    Dave

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    I personally don't agree that 29"er would at a disadvantage in any sort of turns. IMO most trails don't feature a single turn where 29" is hampered in any way. Most turns the 29"er will just roll through at higher minimal velocity, higher average, higher entry and higher exit. Swapping bikes with buddies clearly shows this. Even Fisher/Trek pro's have reported that although the 29" can feel slow, the one riding it just pulls away on twisty bits. Of the four 29ër I own, at least 2 are faster in tight consecutive corners than any 26"er I've ever tried.

    It would be nice to try the 2 PT wheels in one bike, for instance a Surly 1x1. 29"er heavier from different wheelsize, as it should be. At least for continued climbing it would make sense, riding position identical, etc, just BB height a bit different.

    I think I'm starting to understand how the PT reads or calculates power. Now if the PT doesn't read consistently throughout the torque range, this might disadvantage one wheelsize, hmmm...
    Still I think that possibly a 29ër covers a little bit more ground with the same power due to tire deformation.

    Would the Fuel climb/roll so much more efficiently that a light (flexy?) softtail?

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    yes indeed

    Quote Originally Posted by hairball_dh
    ...but they all lead down roads that aren't good subject matter on this board. Hit me on my blog if you'd like to pursue this further. It's all about training with power - and I've got about as much experience as anyone with power on an MTB. It will get a lot of yawns here though.
    The talk is starting here however...look at the responses so far. We can take this back to wattage or your blog if you like.

    To all who lurk here...when Harris says he has about as much experience as anyone with power on a MTB.... Please understand that this is a vast understatement.

    Thanks for the info, and suffice to say we agree that its not about what is best....its what is best FOR YOU (each individual). And the answer is unique to that individual (I suspect).

    I have my answer.

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    Quote Originally Posted by Cloxxki
    I personally don't agree that 29"er would at a disadvantage in any sort of turns. IMO most trails don't feature a single turn where 29" is hampered in any way. Most turns the 29"er will just roll through at higher minimal velocity, higher average, higher entry and higher exit. Swapping bikes with buddies clearly shows this. Even Fisher/Trek pro's have reported that although the 29" can feel slow, the one riding it just pulls away on twisty bits. Of the four 29ër I own, at least 2 are faster in tight consecutive corners than any 26"er I've ever tried.
    I wouldn't even begin to debate this. I trust in your experiences, and also in mine. I've seen your picture - you're up there in the clouds! I'm not that tall...perhaps that is the difference. In any case, some will like bigger wheels more than others, for many different reasons.


    I think I'm starting to understand how the PT reads or calculates power. Now if the PT doesn't read consistently throughout the torque range, this might disadvantage one wheelsize, hmmm...
    No worries there, the PT is a great instrument at all sorts of torque values. Besides, the actual torque values will have more to do with a riders strength than the wheelsize. The wheelsize difference is about 10%, but the difference between say, a 110 lb female and a 200 lb male could be 50%, or much more. The rider applies the torque...
    Still I think that possibly a 29ër covers a little bit more ground with the same power due to tire deformation.
    That is the entire point of testing - to catch all the factors at once.

    Would the Fuel climb/roll so much more efficiently that a light (flexy?) softtail.
    That would surprise me greatly. The Dos is quite stiff - if you recall MCs initial review of the frame he thought it was as stiff as a HT. I don't think it's quite that stiff, but it sure isn't flexy. It *feels* as though it nips my accelerations which slows me down over the long haul. But I don't trust my *feel* on 29ers anymore
    Dave

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    I used to have a really ineficient VooDoo Canzo (Unified Rear Triangle 3.75" travel design). Stupid damper. On offroad flats, the thing was unreal. On tarmac too, actually. With that experience in mind, I can see how possibly a popular bike like the Fuel somewhere hold an advantage over something unprove as a Scandium hardtail. Laptimes on tarmac I set with the VooDoo Canzo have been very hard to match on a super light Giant TCR road bike.
    With your experience in testing, can't you get pretty much identically set up bikes from Fisher or Kona to do even more fairer comparisons?

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    Quote Originally Posted by Cloxxki
    With your experience in testing, can't you get pretty much identically set up bikes from Fisher or Kona to do even more fairer comparisons?
    I wish! Seriously though, I'm not so sure big bike companies would want detailed studies done. They are doing great on marketing/word of mouth alone. Why confuse the issue? What if the studies don't produce the results that is best for sales? There are also inumerable conditions under which testing could be done. Its way more than I could chew off. I know my Dos is faster than my 292 was, and now I know my Fuel is faster than my Dos...I'm satisfied.

    Besides, speed is probably only important to 5% or so of the MTB crowd in general, its more about fun for most I think than suffering, but I could be wrong. There are other reasons 29ers are great - things like allowing new riders to clean stuff they couldn't otherwise clean, less OTB action and the like.

    But I haven't asked Kona, GF or anyone else for that matter...any manufacturers out there listening that would like to supply some bikes for testing purposes??
    Dave

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    Quote Originally Posted by willtsmith_nwi
    Yes, a smaller wheel will accelerate faster ROTATIONALLY. LINEARLY, each rotation of a larger wheel gets you farther. If you do the math, you'll find out that the faster rotational acceleration of the smaller circumference vs the slower acceleration of the larger cirmuference are exactly the same.
    Wrong. At the same linear speed, large wheel with a mass proportional to its radius (lets assume all mass in the rim of the uniform thickness) will have larger stored kinetic energy - so the same work will accelerate you slower with a larger wheel. Integrating this to get the distance travelled under steady power does not change this obviously.

    That said, it does not really matter in this case. Rolling resistance, tracation and momentum loss while rolling over obstacles seem to be more important.

    P.S. I think the biggest diffrence is in you physiological response (I feel it pedals smoother, and that is the spikes in muscle tension that really do get you tired), and in your head... On a full suspension (> 2") though I prefer 26".

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    wow

    Hey hairball thanx for your report (although I don't understand it) :-).
    I'm a fellow that is in almost the same situation as you. I raced a top fuel, and grabbed a fisher paragon 29er simply for a trail bike, as the fuel was taking a beating. I would say I have your average racer build...5'10 160lbs.....After riding the Paragon for a couple of weeks...I punted the Fuel. Simply got rid of it, and will now be racing the Fisher. You mentioned FUN. I simply had more fun on the paragon while training off road. I have no idea why. It felt less twitchy (more stable), and it kept me excited. Once again I have no idea why....but this all seemed like a good thing to me. I wasn't any slower or faster on group rides, and my individual times, and HR's are basically the same...BUT - I have a lot less "oh s**t" moments on the paragon...It's almost like I can turn my brain off when riding it and concentrate more on just going fast.....So I am a full blown objectivist from the start...straight out of the Ayn Rand school of reality...so I realize that everything I just said was subjective..barring times.

    My questions are..and this is my perception based on your words.

    1. You ragged on the Pepperdine article mentioning that it was unsupported...But who are you? You are just some guy with a powertap doing 2 climbs, and claiming that it is objective, and valid? How is this possible?

    2. How does it not make sense that you turned more power on one bike than the other, thereby going faster? The only thing that can be gleaned from that is somehow the 29er..."didn't allow" you to turn as much watts. That is almost mindblowing that a guy as smart as yourself wouldn't step back and say "there is a problem with this data"....

    3. You mentioned from the start that you really wanted to get down to the truth on what was faster. This can only mean that A. You had no real idea (race results) whether or not a 29er was slower....or B. your subconscious was somehow presenting a negative response in the form of a question.
    Why would you question if you were faster....especially if you were having so much fun? Race results didn't tell you anything?

    It just seems to me that you really wanted to pick apart the 29er, and maybe didn't really have any interest in objectivity, because your brief testing data is totally inconclusive, and subjective.

    Wouldn't it have been much easier to say...I felt like I was slower on the 29er so I went back to a 26? There is nothing wrong with that at all.

    So to finish up - I'm not a 29er freako....I'm riding one right now because I'm having fun. I have a few bikes from road to 26. Bikes are bike to me. I'll race all of them. But since I try to be objective, I found it really strange that you picked apart the pepperdine article, as subjective blather, and then you give us two little tests that really don't say anything, and are for the most part totally subjective in nature.
    Oh and I'm a training peak guy myself! Keep up the good work on the racing.

    Still confused as to why you turned more power on the fuel, and are surprised you went faster? :-)

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    I want to see a perfectly objective electro motor propel a bike around a track. Swap motor between bikes, and keep checking power output With the motor driving the rear rim, placing it precisely, even the wheelsize difference can be negated.
    It won't be an easy experiment to setup, but don't you love the idea of racing about a mountainbike with an engine?

    Combustion might work as well. Bigwheel has experience sticking those to 29"ers already. A combustion enginge might be constant enough for testing already?

    :-)) Imagine having to shift the gears as usual, because the engine "pedals" like a rider in the last lap of a 24h race, all constant power, no spint power left. Smart shifrting required to keep the engine in it's ideal power band.
    Specially prepared full power laps where the engine won't stall should be really cool and interesting already. getting accross a muddy section, a sand drift, etc. How low does it take with a precise amount of power?

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    To Jekyll and Hyde:

    Quote Originally Posted by Tbonius
    Hey hairball thanx for your report (although I don't understand it) :-).
    I'm a fellow that is in almost the same situation as you. I raced a top fuel, and grabbed a fisher paragon 29er simply for a trail bike, as the fuel was taking a beating. I would say I have your average racer build...5'10 160lbs.....After riding the Paragon for a couple of weeks...I punted the Fuel. Simply got rid of it, and will now be racing the Fisher. You mentioned FUN. I simply had more fun on the paragon while training off road. I have no idea why. It felt less twitchy (more stable), and it kept me excited. Once again I have no idea why....but this all seemed like a good thing to me. I wasn't any slower or faster on group rides, and my individual times, and HR's are basically the same...BUT - I have a lot less "oh s**t" moments on the paragon...It's almost like I can turn my brain off when riding it and concentrate more on just going fast.....So I am a full blown objectivist from the start...straight out of the Ayn Rand school of reality...so I realize that everything I just said was subjective..barring times.

    My questions are..and this is my perception based on your words.

    1. You ragged on the Pepperdine article mentioning that it was unsupported...But who are you? You are just some guy with a powertap doing 2 climbs, and claiming that it is objective, and valid? How is this possible?

    2. How does it not make sense that you turned more power on one bike than the other, thereby going faster? The only thing that can be gleaned from that is somehow the 29er..."didn't allow" you to turn as much watts. That is almost mindblowing that a guy as smart as yourself wouldn't step back and say "there is a problem with this data"....

    3. You mentioned from the start that you really wanted to get down to the truth on what was faster. This can only mean that A. You had no real idea (race results) whether or not a 29er was slower....or B. your subconscious was somehow presenting a negative response in the form of a question.
    Why would you question if you were faster....especially if you were having so much fun? Race results didn't tell you anything?

    It just seems to me that you really wanted to pick apart the 29er, and maybe didn't really have any interest in objectivity, because your brief testing data is totally inconclusive, and subjective.

    Wouldn't it have been much easier to say...I felt like I was slower on the 29er so I went back to a 26? There is nothing wrong with that at all.

    So to finish up - I'm not a 29er freako....I'm riding one right now because I'm having fun. I have a few bikes from road to 26. Bikes are bike to me. I'll race all of them. But since I try to be objective, I found it really strange that you picked apart the pepperdine article, as subjective blather, and then you give us two little tests that really don't say anything, and are for the most part totally subjective in nature.
    Oh and I'm a training peak guy myself! Keep up the good work on the racing.

    Still confused as to why you turned more power on the fuel, and are surprised you went faster? :-)
    Tbonius I see you have a split personality thing going on, but hey, this is my day to field endless questions, so here goes.

    The pepperdine study - elighten me how I said it was unsupported, I don't recall doing so. It is not published (only an abstract is available), so we don't know under what conditions they found the 29er to be faster. Course? Rider? Dunno. You want to base a decision on that?

    I have a lot more than 2 climbs worth of data. Check out the equipment link on my blog and get back to me - there's a lot more updated info.

    Sure, more power =- more speed. That's simple. I found there to be a dissproportionate gain in speed for a small gain in power. I've described why in several places...
    Dave

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    huh?

    Any strong objectivist will realize that subjectivity exists in the world....It's impossible to not go by feeling occasionally..BUT ANYWAY
    Objectivsm simply means that a reality exists outside of our mind.

    So I fail to see how your tests are truly objective?

    I only see three "controlled" tests....and I use this term loosely.

    I see phrases such as this:

    "I added the red rectangles to show the "what if" scenarios. Consider the case where average power over a lap is 188 watts. Based on this data, a lap time of 67 minutes would be predicted for the Fuel, while the predicted time for the Dos is just under 69 minutes. Looking at it from another angle, for a lap time of just under 69 minutes, I'd have to average 175 watts on the Fuel but 186 watts on the Dos."

    followed by

    "So there you have it. It's cut and dried in my mind."

    and here's a quote from where you declared a tie.

    "Normalized power was just enough higher in the Fuel tests to indicate I had a bit more snap in the legs on that day. In rolling terrain, it is very important where you put the power down, and how much at a time. On the Fuel's day, I just had a bit more to give on the steep ups, and rested more on the descents. The averages were the same, but Pnorm tells all...another factor that may have attributed to faster times on the Fuel was that I got 3 runs in on the Dos 5 days prior, so I was more familiar with the trail. The Fuel did feel faster in the tightest terrain, oh wait, that's subjective, nevermind."


    Excuse me bro. I'm not here to dog on you. I could care less if you like a 29er or not. I'm just trying to understand your testing in the face of objectivity. I like data just like the next guy.

    I see a lot of "what if's" ...."normalizing"......"stomp testing for error correction" etc.....

    Regarding the Pepperdine test. Unsupported, unpublished whatever! You are dogging the paper because it apparently cannot be quantified. But neither can your tests? How do I know you aren't just a troll? How do I know you really even did these tests? How do I know how you felt, were you sick etc..?. How do I know you don't have burned out BB on the 29er and it's killing you etc.....etc....etc....

    I've done testing that produced bigger differences in results on the same bike than you have on 2 different bikes.....

    I'm just trying to understand.

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    Wink Let's not explode here...

    Quote Originally Posted by hairball_dh
    Tbonius I see you have a split personality thing going on, but hey, this is my day to field endless questions, so here goes.

    The pepperdine study - elighten me how I said it was unsupported, I don't recall doing so. It is not published (only an abstract is available), so we don't know under what conditions they found the 29er to be faster. Course? Rider? Dunno. You want to base a decision on that?

    I have a lot more than 2 climbs worth of data. Check out the equipment link on my blog and get back to me - there's a lot more updated info.

    Sure, more power =- more speed. That's simple. I found there to be a dissproportionate gain in speed for a small gain in power. I've described why in several places...
    Now guys...as Dave said, it's been refreshing to have a "civil" discourse, let's try to keep it that way. I think Dave's done some way cool testing. He's gone a lot further with what most folks here feel is the best way to get an answer (Cloxxki and his combustion engine aside).. . We all have opinions and that's exactly what they are...no matter how much testing is done.

    I myself am more in your camp Tbonius...I understand the physics, I see the test results and then I rode a 29er. Only once mind you and for less than 5mins. But it felt faster, it felt like it rolled smoother and I don't know if that's a psychological impact or whether something really is going on mechanically that is hard to quantify.

    I guess bottomline has been my question all along. If there were an advantage to a 29er, then NORBA and WC would have to penalize them when they ran with 26er's and Specialized and all the high end teams would be racing them. Since they haven't and aren't I can only assume they know something we don't or the jury is still out.

    I think the jury is still out!!!!

    Play on...play nice.

  76. #76
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    Moving along

    Quote Originally Posted by dugodugo
    So you're telling me Specialized has to get it's ass handed to it by Fisher before they adopt a 29er??? Uhmmm....something there ain't right. If 29er's are faster which I believe we're starting to get a concensus on, then what's up with the race teams??? I'm not sure of the rules but I thought it was pretty much "run what ya brung" at least in NORBA. Is World Cup different??? Do they limit 29er's??? And if not, why haven't more race teams jumped on this advantage???

    That's what has me going!!!!
    29's were illegal in World Cup races until a couple of years ago. GF has changed that.

    As for the race teams, Fishers Team is using them, and won the 24 hr national championship and SS championships. I don't think the bigger names are "allowed" to use 29ers yet
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    Wink It's all good

    Quote Originally Posted by hairball_dh
    I wish! Seriously though, I'm not so sure big bike companies would want detailed studies done. They are doing great on marketing/word of mouth alone. Why confuse the issue? What if the studies don't produce the results that is best for sales? There are also inumerable conditions under which testing could be done. Its way more than I could chew off. I know my Dos is faster than my 292 was, and now I know my Fuel is faster than my Dos...I'm satisfied.

    Besides, speed is probably only important to 5% or so of the MTB crowd in general, its more about fun for most I think than suffering, but I could be wrong. There are other reasons 29ers are great - things like allowing new riders to clean stuff they couldn't otherwise clean, less OTB action and the like.

    But I haven't asked Kona, GF or anyone else for that matter...any manufacturers out there listening that would like to supply some bikes for testing purposes??
    Dave...thanks for the input...your comments I believe really have hit at what we're up against. 29er's have their advantages and so do 26ers. Which one is faster on which track all depends on the design of the course. Its crazy to say one has a dominant advantage over the other.

    In general, for the recreational rider, the 29er provides advantages that they themselves could appreciate....that about sums it up for me.

    Thanks....

    Now come on Gary, poney up for Dave!!!!

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    Yea...human beings are completely untrustworthy, and susceptibble to way too much physical and physchological interference. A guy who has an emotional opinion/question that he may in fact be slower on a 29er (or 26er) and then does his own personal comparison....let's talk about self fulfilling prophecies. How many times have we heard a young athlete state "I can't do it!"...only to know damn well that they can....and then see them do it. Full suspension bikes are supposedly faster also than hardtails. Julien Absalon will continue to destroy people on his hardtail....go figure. He probably "feels" faster on it.

    It's impossible to to testing for all to look at and claim objectivity, and then backtrack. It's nonsensical.

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    Quote Originally Posted by juice0276
    29's were illegal in World Cup races until a couple of years ago. GF has changed that.
    Actually, The UCI was wondering about the whole 29" deal. may have received requests from individuals or other companies to look at the matter. Since they had a relationship with Gary (he picked up a World Marsters Gold medal not to long ago), they asked his to be the 29" bike's advocate. I got to do some document writing, Gary came up with better reasons, offered them to the UCI and they thought it was a good idea to allow 29" bikes from now on. Main reasons : less crashes, fairer for tall riders, and larger starting fields.

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    ranting zealots

    Tbonius-
    Your ranting about a lack of objectivity is ridiculous. Whether you agree with his methodology or decidedly cautious, qualified conclusions, it is absurd for you to ignore the fact that this represents the closest thing anybody has done to an objective analysis. You just don't like his conclusion so you chose to attack his evidence. Lame.

    This 29er evangelism is tiring. You zealots act like everybody who disagrees with you is an idiot. Most of the rabid 29er fans never even spend more than 5 minutes on a 26er again to "prove" that the 29er is better. Guess what; it takes time to get used to the little wheels again. Maybe you need to give it a real try.

    Cloxxki, you also leave no room for conflicting opinions. This coming from a guy who lives in the flattest country known to mankind. -

    "IMO most trails don't feature a single turn where 29" is hampered in any way. Most turns the 29"er will just roll through at higher minimal velocity, higher average, higher entry and higher exit. Swapping bikes with buddies clearly shows this"

    If you can't find a single turn where a 29 is hampered in any way, I'd say you haven't seen much of a variety of corners, or your skyscraper height makes all 26ers fit like crap on you. At least qualify your completely subjective opinions in some way.

  81. #81
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    Moderators, please shut thread down now...question has been definitively answered!

    Quote Originally Posted by FoShizzle
    In addition to frames being a bit bigger on the average, the wheels are bigger so when you go with something like colored spokes on say an Industry Nine wheelset, the 29er wheels and larger frame will provide more room for bling.
    aaaannnnnndddddd, we're done with this topic. Next question.
    disclaimer: i (NO LONGER) live with my mom...

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    Yup, looks like the Show done Fizzled!

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    Nice

    Quote Originally Posted by heavyg
    Tbonius-
    Your ranting about a lack of objectivity is ridiculous.

    This 29er evangelism is tiring.

    Cloxxki, .... Swapping bikes with buddies clearly shows this"

    This thread is getting rich. There are some really stupid things being muttered on line (yeah yeah some of them were from me).

    The thing about swaping bikes is possibly the best. I mean really, how can anyone really expect to hop on a borrowed bike that is likely not fitted to anyone, and hope to conduct any worthwile test?

    Similarly, I hoped into a Lexus the other day and it rode like crud...therefor all (yes ALL models, colors etc.) Lexus are junk...to bad my wife had the seat in her position and I was sharing the seat with a bag of groceries the whole time...never-the-less my conclusions are rock solid.

    Kill the thread...we are done.

    You ride what you like...I will ride what I like...Why is it that everyone feels the need to convince the world that what you are riding this week is the best of all time? Are we trying to convince ourselves?

  84. #84
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    Thank you

    Thank you! all that good info and I am still just going to have to do my own investigating.

    Just kidding, 29'er all the way.
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    Wink I'd say so, but it was interesting.

    Quote Originally Posted by mcd
    aaaannnnnndddddd, we're done with this topic. Next question.
    Yanno...I really appreciated this little discussion. It showed that there are folks very commited to their views and some very commited to trying to find the facts. It's always tough, scientific theorems and proofs are always difficult to defend and even harder to keep objective with experimentation.

    I myself learned a lot and realized that when you get right down to it, it is about the ride and having fun (or being competetive, which can be real fun). For me, I'm wheeling around on a 22lb HT right now, soon to get my 32lb gravity sled together. Next winter I'll definitely work on a 29er and I guess thats what it's all about. The next adventure and the next experience.

    As humans, I don't think we're ever really satisfied, or maybe it's just that we're really curious. Yea to some it is the next greatest thing (gotta have the Bling), but to me it's more about the feeling of riding and how it can feel so different on different bikes.

    I appreciate everyone's participation and until next time, remember, no one is really right and no one is really wrong, we all just have different ways of seeing the same light...

    Carry on....

    Dugo
    Last edited by dugodugo; 02-24-2006 at 08:34 AM.

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    whoooooa there tiger.

    HeavyG et al, -If I'm a 29er zealot than Lionel Richie is a heavy metal god. I'm not the one trying to be objective. Hairball is. I'm not claiming objectivity. I've never raced a 29er in my life and have only owned one a few months. I just don't understand how he can down the Pepperdine test, and give us his test, and claim that it is more "objective"......He's using a powertap. Powertap's are great, but explain to me how they actually determine if one machine is faster than another? As far as I know they simply reflect a persons individual power. The word "individual" is very important here. If I came off ranting, my apologies but it hardly makes sense for you to declare me ranting, and then RANT yourself? Are you sure you aren't a 26er zealot??? :-) I'm a bit of a geek and like to look at test results, I'm just failing to see how his testing data makes any sense.

    One of the glaring problems I notice is regarding bike to bike. It would seem logical that if one machine were actually slower than the other, it would take MORE power to get it up to the speed you were accustomed to, AND a higher heart rate....I would logically expect to see the same average times, BUT with a 29er bike having higher power levels, and higher heartrates. It would be analogical to testing your 45 lb freeride rig, against your XC race bike. You can make it go as fast, but it will kill you......There is absolutely no conclusive evidence regarding 650cc- vc. 700cc wheels on the most controlled environment there is...Uphill pavement. Mr. Armstrong is about the most anal person in the world. If a 650cc wheel went faster uphill....why wouldn't that dude be riding one? Why did most tri-athletes forego the 650??? Some say eqipment availability ...who knows.
    The only scientifc data I can find on wheel sizes usually involves car wheels. Most tests agree that it take more to get a bigger wheel going, and MORE to slow it down.....I find this telling. I think having a wheel that is harder to slow down is interesting in the face of an endurance event...but I still have no idea which machine is scientifically faster. Cloxxis funny little experiment may actually make sense after all. Mit should really work on this...or somebody.

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    Wine me, dine me, twenty-nine me- thank you all for the most entertaining thread I've stalked in many months!

    ;{)

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    fair enough

    Tbonius-

    I appreciate the last post and it does help me understand your position more clearly. But I am not really a 26er zealot, as I wrote this as my admittedly empricial, subjective "conclusion" earlier in the thread:

    "I think that 29ers are better for 80% of the people who ride hardtails, 90% of those who ride rigid and/or singlespeed, but more like 50% of those who prefer FS. Depends heavily on local terrain, obstacles, and skill level/ body style of the rider."

    I really only have one goal in posting in debates like this: I am trying to help out the dude who is sitting there trying to figure out if buying a 29er is the best choice for them. That is exactly where I was 18 months ago, and this board is THE reason I decided to take the plunge. I never had the chance to ride or even see a 29er before I put down my $1600 for a 293.

    Now that I have more perspective and experience, I feel some sense of duty to share my opinions purely in order to help out another "newbie". I have no regrets about owning three 29ers in the last year, but I think there is a good bit of closed-mindedness about the minor disadvantages of rollin' with the big wheels. Kind of propaganda-like.

    Other than that, I still generally think this board and its regulars are truly outstanding in terms of offering solid advice, perspective, and experiences.

    Peace out

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    We are in agreement.

    It is totally worth five minutes of our time to reflect on different bikes, and I think it is all about spreading good juju for the lifestyle...and I mean CYCLING lifestyle....not 29er, or SS, or 26er for that matter. There are a lot of beginners etc..that lurk these boards who are trying to make decisions, and you're absolutely right. There is a lot of 29er propaganda as innocent as it may be......my totally "subjective" conclusion is very much in agreement with you....riding styles, terrain, course length and topography can affect everything and most certainly will.....but this may be where the heart of the matter lies, as I am convinced it isn't much different than singlespeeding. Do we have to "learn" how to ride and race a 29er correctly, understand it's advantages, disadvantages etc...before we can even begin to accurately test? We all know by now that SS riding and racing is completely antithetical to geared riding. You simply can't ride a SS like a geared bike, and most people will report that they had to learn a completely different riding style in order to grasp SS in it's fullest. Climbing anyone? So my concern is that a lot of people jump on a 29er and try and ride it exactly like the 26er that they have been riding for years, and then want to blame the bike. Then again....why should a person want to learn a new riding style? Lot's of questions...not many answers.

  90. #90
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    I just don't see specific situations where I would feel "damn, a 26incher would have been just the tool for this". Very maybe when 2 root are very awkwardly(sp) spaced so my 29" wheel just gets stuck in between. That magical ditch exacly the shape of a 29" wheel which the 26" would have rolled through.
    Corners? My 29" race bike has more top tube yet less wheelbase than an equavalent 26"er.And the power required to actually turn the wheel? I can't really tell anymore, and for sure it won't hold me back.

    Everyone will agree that a 20" wheeled folding bike won't do too well in corners, nor tough terrain (be it rocks, sand or mud). The saved pounds probably aren't even worth the increased rolling resistance, even on climbs. The 650c Lance example was very good. If in one TdF stage it were expected to be faster, for sure Trek would build Lance a custom 650c OCLV for the day.
    As nice as Powertabs are, they may not be a very practical device for this type of testing. 2 different units, very unequal bikes.

    On the weight forum there are people doing many hill-roll tests to see how fasts various tires roll. Gravity is the same all day long, and dry trails are pretty constant in quality. Take a hill, stand still, let go of the brakes, and see how long it takes to roll down. A nice moderate slope that sees you rolling a race-type average pace (10-15mph) is pest, as aerodynamics don't come into play too much. the amount of energy gravity puts into your vehicle is simply a sum of hill angle and rider+bike weight. "Only" RR and air drag hold you back. RR being the main thing, at least on typical riding speeds.

    I'd love to use a wide very mildly downsloped fire road to test 29" and 26" against each others on a snowboard-style slalom course. I'm positive the 29"er rolls more efficiently through turns. When I yank the bars left and right, the 29"er rolls mich faster afterwards than teh 26"er does, even if it's tires are faster.
    A long twisty downhill where more braking is involved (same typical average speeds preferably) would be nice too. But, then the pilot has to be comfortable with all kinds of bikes, and able to take the maximum out of it. I've had a guy on my 29"er who just barely moved along over the trail, and on his scary narrow-bar'd 26"er is a god on wheels. I've also seen a guy throw a leg over my bike and just disappear aroud the next corner, not to be caught back. First real 29" experience for him too.

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    Cloxxi, I think the point I was trying to establish is that whether or not a 29er is faster in a corner than a 26er, I would say they do corner differently.....but does "differently" translate to slower or faster?

    Contemplate this.....it's probably close to established fact that a 29er will wind up slightly slower..BUT so will a heavier 26in wheel over a lighter 26in wheel....now lets say you are a 26inch rider who has developed the seriously bad habit of "parking it" into corners, and then "sprinting out" while racing or riding or whatever. When this same rider hops on a 29er he's going to notice "something" when coming out of that corner...even if the larger wheel circumference is gaining the same ground - it's simply going to "feel" slow to this guy., and it really has nothing to do with the bike...it's completely riding style. He can get away with it on a 26er....either because he's so used to it, or maybe because his perception is flawed when he sprints out of a corner - BUT it's still going to affect his judgment. Styles make fights I guess, and in the tight corner department, I think a 29er may expose some flaws in your technique - giving you a false impression...the same way a hardtail makes you pay for a bad line, when you are used to plowing over everything on a FS bike.

    I just think that in the few months that I've been riding a 29er..my riding style has actually changed a bit. ....then again I could be crazy.

    One thing that I think everyone would agree on is that a 29er hardtail is more comfortable than a 26er hardtail. I haven't found one person that disagrees with this.......that tells me a little bit.

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    I don't share your assumption. I'd like to see what happens when you have a downsloped twisty section and the bikes in it, stopwatch running. I drop 26" singletrack heroes on tight singletrack. But I can't imagine that my skills have grown past what I previously thought humanly possible. A couple good tests will tell. Especially a sequence of 15-20mph 90º corners would be interesting. People on my wheel tend to either lose me or control. Never happened when I rode 26".
    If 29"ers prove to be slow in corners, cool, I recently won the Dutch SS title on a 7km track with ~200 corners, most all singletrack. Maybe I'm the new local singletrack god :-) Really, it was the bike. I brake less and pedal less.
    Perhaps if two riders (on the equal Powertap bikes) of equal weight ride a lap around that track together, it would show some interesting differences. I can freewheel sections that 26"ers have to pedal through to stay with me. I can rain through corners 26"ers have to hold back for.
    Maybe othis track is unique, but who know it just didn't expect a 29"er to get around it. I surprised my singletrack hero there, by warning him verbally for the attack I was to place, and he still had to let me go. He was the fitter rider for sure, I weighed 30lb more.

  93. #93
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    Quote Originally Posted by heavyg

    "I think that 29ers are better for 80% of the people who ride hardtails, 90% of those who ride rigid and/or singlespeed, but more like 50% of those who prefer FS. Depends heavily on local terrain, obstacles, and skill level/ body style of the rider.
    I never had the chance to ride or even see a 29er before I put down my $1600 for a 293
    If that same 293 is now $500 more, what then ? I would probably prefer a 29' FS, but I'm not going to overpay for one. Seems like GF is trying to re-coup their losses on so many cracked Sugar frames by passing it on to the new FS 29er customer.
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    after lurking through it all...

    here are my thoughts on the subject. im no joe racer, just a guy that loves riding mtbk's. i own 4 steel hardtail 26er's 1 softail 26er and 1 steel hardtail 29er. for me the 29er has several advantages.
    1) im a big guy (6ft 2in, 250 lbs) the bike feels appropriate.
    2) i hate the idea of fs, 29er's let me ride longer and stay fresher w/o the complexity of fs.
    3) corners, climbs and descends better the more technical the trail the better.
    4) better through wet leaves, roots and rocks than a 26er. in the east, this is huge.
    5) better through sand AND mud on LI,NY where i live there's plenty of both.
    6) is the equivalent of riding an SUV off-road the 26er is a car riding off-road. just mho.

    ive never ridden a fs bike so i cant comment on the advantages or disadvantages when compared to a 29er. i do know this though, there's a group that nite rides every tues. and thurs. that has some of the fastest riders around. i get dropped by these guy's (and a kool woman) every time i ride with them, with out fail. i rode with them on my 29er for the first time about a month ago. did they drop me, yes they did but it took about 45mins instead of the usual 15mins. i was dying (these guy's ride a lot more than me, or most people for that matter) but definately convinced that for me the 29er was faster. for some one else the opposite may be true, but ive found the perfect ride for this dreadlocked clyde !.
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  95. #95
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    Quote Originally Posted by FoShizzle
    yeah....to part of Pacman's point I believe, the real advantage to 29er is that, generally speaking, the stuff is bigger. In addition to frames being a bit bigger on the average, in concert with In addition, the wheels are bigger so when you go with something like colored spokes on say an Industry Nine wheelset, the 29er wheels and larger frame will provide more room for bling. Other than that, no real difference.
    well said (typed..?)- Ride what makes you HAPPY, and lay off the "29er's make it easier for noobies to clean stuff" because its bullsh!t. Sigh, how much does a powertap cost anyways, multiply that by 2 and you get overanalysis, no offense intended...back to my zombie movie
    It's not hip hop, it's electro.....

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    hairball_dh has outdated information as 292 has old geometry G I and thus aobut 87mm of trail, let him try a G II hi-fi with 72mm with light wheelset and jet9 or any other qiuck handling and light 29ers.

    What else has been improved till now?

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    I remember cyclingnews attempted to do a test on 26ers vs 29er, however no further attempts were ever made. I wish there was a way to do a test, but it didn't involve so many variables, i.e. the rider. The closest thing for a test would be probably hiring a set of twins who share the same athletic ability and background in skills and then giving one of them a 26er and the other a 29er. Even then the test would not be 100% accurate, but it would probably be the closest thing. By the way I am all for the 29er revolution since I plan on getting a Superfly.

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    Esteemed 29er brethren,

    Lately I've been struggling with finding a simple and persuasive rejoinder to the oft-heard claim that 29ers are less "quick" than 26ers -- that they are harder to accelerate.

    Some historical discussion here at MTBR have attempted to address this, with varying degrees of clarity. In light of that, I submit the following contradiction and seek an explanation that I can weild with authority:

    On the one hand I think the problem should be simplified to ask "what is the difference between the two wheel sizes DUE TO SIZE ALONE", and not complicated with mass and gearing and such. (Don't care to know if lighter is quicker than heavy, nor if the right gear is quicker than the wrong gear.) So I think that means that the WORK required to move bike and rider from point A to point B is obviously the same, regardless of wheel size.

    But, on the other hand I am often thrown a challenge by the "LAW OF INERTIA" whereby there is an ARITHMETIC (squared) relation between moment of inertia and radius which is, I think, overwhelmed by the LINEAR relationship between radius and circumference, to which Mr. WillTSmith points in this discussion:

    http://forums.mtbr.com/showthread.ph...r+acceleration

    The moment of inertia formula for wheels can be aproximately simplified this: I=mrr (or I=mr squared) and from this I calculate that moment of inertia of a 29er is about 24% greater than moment of inertia for a 26in wheel (all else being same). Unfortunately, the "roll out" difference is only 10%. That is, for each revolution the 29er only goes a relatively little distance further. Despite my 29er bias, I can't reconcile the two in a way that has them tied.

    Can you help me here?

    For reference, in the same thread just a couple posts earlier I see that Dr. Welby claims that when you compare vehicles with different size wheels, the "wheel radius terms drop out". Can someone show me that one?

    Thanks in advance.

    Sincerely,

    29erBidwell

  100. #100
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    Idea! Simple (?) Physics of 29er Wheels

    Quote Originally Posted by 29erBidwell

    For reference, in the same thread just a couple posts earlier I see that Dr. Welby claims that when you compare vehicles with different size wheels, the "wheel radius terms drop out". Can someone show me that one?
    Pardon if this has been spelled out before but I couldn't read *all* the posts on this topic, could I?

    Anyway, let's use some basic physics to see what relationship the wheel radius has to speed. We'll set up a simple, classic physics problem where the two wheels in question 26 and 29 are positioned at the top of an inclined plane. We'll also ignore friction for the time being. Both wheels are released from rest and roll to the bottom. Which one gets there first?

    Using simple energy we all (?) learned in Physics I...

    Total Energy Before (at the top) = Total Energy After (at the bottom) ---> The law of conservation of Energy!

    Since both wheels are at rest and at the same height, they start with Gravitational Potential Energy (GPE) only. At the bottom, both are translating and rotating so they have Translational and Rotational Kinetic Energy (TKE, RKE). So...

    GPE = TKE + RKE

    Substituting formulas we get...

    mgh = 0.5mvv + 0.5IWW -->(m=mass; g=gravity; h=height;v=translational velocity, I=moment of inertia; W=angular velocity)

    Both wheels are thin hoops so I=mrr. We'll also use the trig transform that W=v/r.

    mgh = 0.5mvv + 0.5(mrr)(v/r)(v/r)

    Cancel the masses on all terms and cancel the r's on the RKE term and we get...

    gh = 0.5vv + 0.5vv or gh = vv or really gh = v^2.

    So who gets down first? Both have the same gravity and initial height so...... Its a tie!

  101. #101
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    What? All I know is my bike is fast. If you get one, you will think yours is fast as well!
    Life, liberty and the pursuit of singletrack.

  102. #102
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    Quote Originally Posted by mtb 4ever
    What? All I know is my bike is fast. If you get one, you will think yours is fast as well!

    winner of this weeks 2+ year old thread resurrection!

    and you got that right.
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  103. #103
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    Quote Originally Posted by tbaier
    So who gets down first? Both have the same gravity and initial height so...... Its a tie!
    ...unless you include roling resistance. Every known surface, even tarmac or smooth plane has burrs and they will minimally encumber the smaller one. For instance go all lenghts to the extremities like a 16" and 36" both the same weight and the same tyre and repeat you test.

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    Quote Originally Posted by Davidcopperfield
    ...unless you include roling resistance. Every known surface, even tarmac or smooth plane has burrs and they will minimally encumber the smaller one. For instance go all lenghts to the extremities like a 16" and 36" both the same weight and the same tyre and repeat you test.
    Yeah, my skateboard is pretty slow through the rocky sections around here.

  105. #105
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    I'm new to the 29'er thing, but I've noticed that they pick up speed remarkably faster rolling downhill - dirt or street. Unfortunately, I can't provide a physics equation to explain why, but the 29'er def. has an advantage!

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    yes...

    Quote Originally Posted by Davidcopperfield
    ...unless you include roling resistance. Every known surface, even tarmac or smooth plane has burrs and they will minimally encumber the smaller one. For instance go all lenghts to the extremities like a 16" and 36" both the same weight and the same tyre and repeat you test.
    Of course. I was only responding to the guy's question from before... he wanted to know how the radii cancel out of the basic energy equation. Rolling friction is certainly a factor though coming more from the axle than the tire, oddly enough. Try http://hyperphysics.phy-astr.gsu.edu/hbase/frict2.html at the bottom for a brief explanation.

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    The bigger wheel just rolls over stuff much easier - spends less time going bumpity bump.

    I don't buy the angular acceleration/kinetic moment BS. Unless you were using these wheels on a drag car you would never realize the difference between a 26/29 - even if you were, it would still be minimal. They are just not accelerating (or spinning) that fast.

    Someone used the monster truck analogy. That is really the key.

    There's a reason why lawn mowers have bigger wheels now. They're easier to push.

    Which would you rather ride down a rooty, rocky hill, one of those sick all-terrain skateboards with big inflatable rubber wheels or a regular board with small hard wheels? Honestly, I wouldn't try either.

  108. #108
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    Quote Originally Posted by willtsmith_nwi
    Without reason, everyone is wrong.
    Put the bong down.

    What is this thread about, anyway?

  109. #109
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    yes
    plunging like stones from a slingshot on mars.

  110. #110
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    Go figure. I love passin 6ers on the fast downs. They never realize that we got more gear than them. I hammer right til I get to them and then stop pedalin just as I pass them. Things arent always as they seem.
    Rule of thumb- 1 Lb. costs 2 sec. per mile of climb

  111. #111
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    Gravity is much more dependable "motor" than legs. You just sit or stand there, as gravity adds speed to you and you bike. No pedal-induced wandering of the front wheel which gives that false illusion of superior speed. It's just gravity vs. rolling resistance.
    Gravity usually wins, but by which numbers, that's the question.

    Unless the hill is really steep, the acceleration coasting down is more gradual than had it been flat and the legs doing the work. Therefor a rolling advantage already there, becomes more apparent.

  112. #112
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    I love my magic carpet!
    If you were looking to buy a monster truck, you wouldn't buy sub compact wheels for it.

  113. #113
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    I'm a firm believer in the right bike for the terrain. Following that train of thought, my Redline Flight 29er is perfect for the trails I ride. In central Florida, all of the fun trails are remains of old phosphate or limestone mines. As such, we get alot of short steep downhills immediately followed by short steep uphills (the trails basically skirt the peremiter of the pits). On these trails, my SS 29er is almost too much fun. I can zoom downhill and have enough momentum to carry me uphill. It really is a blast compared to my 26" bike.
    Tampa Florida

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  114. #114
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    Quote Originally Posted by dr.welby
    As for having 10% more distance to roll with the same "gear ratio" - it's not the same thing. Think about how gears work. A low gear makes you move a small distance per pedal revolution, a high gear you move a bigger one. Whether you get that extra distance by using a bigger chainring, a smaller cog, or a bigger wheel, it's all part of the same chain of levers that make up your drivetrain. See the esteemable Sheldon Brown's gain ration page:

    http://www.sheldonbrown.com/gain.html

    Absolutely, if you really were gaining 10" per rotation that would be an insane increase. The larger the wheel the more torque is required from the drive train. That equation (wheel surface or aerodynamics aside) should be totally proportional.

  115. #115
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    Forgetting the "mountain" in the mountain bike for a moment, will a 29" wheel have an advantage when riding a paved road? I still don't think i would ever want to take a long trip with one though. If i break down it's gonna be harder to find a replacement.

  116. #116
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    Quote Originally Posted by BearcatSandor
    Forgetting the "mountain" in the mountain bike for a moment, will a 29" wheel have an advantage when riding a paved road? I still don't think i would ever want to take a long trip with one though. If i break down it's gonna be harder to find a replacement.
    a 29er is a 700c is a road bike wheel. Finding parts is as easy as going to a bike shop and getting parts. If they have road bikes they have spokes, if they have road bikes they have touring size tires and tubes you can use. If they have mountain bikes they have all the other parts you could possibly use. Now 650b you might have this issue but this is not an issue with 29ers.
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  117. #117
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    thanks RockCrusher. That explains a lot! (feels and is a newb to mountain biking)

    (reposts other question so it does not get lost back in 2007)

  118. #118
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    Forgetting the "mountain" in the mountain bike for a moment, will a 29" wheel have an advantage when riding a paved road that you would normally use a road bike on?

    (asks the guy who wants to build a touring/mountain bike)

  119. #119
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    Quote Originally Posted by BearcatSandor
    Forgetting the "mountain" in the mountain bike for a moment, will a 29" wheel have an advantage when riding a paved road that you would normally use a road bike on?

    (asks the guy who wants to build a touring/mountain bike)
    you will want to check out this post:

    http://forums.mtbr.com/showthread.ph...ht=salsa+fargo

    might just be up your alley. Set to tour to the extreme but still dirtable.
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  120. #120

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    Quote Originally Posted by tbaier
    Of course. I was only responding to the guy's question from before... he wanted to know how the radii cancel out of the basic energy equation.
    Indeed, that explanation -- complete with all the formulas -- works for me. So long as the wheels are the same weight and both "thin hoops" then they will arrive at the bottom of the incline plane in a tie, regardless of their radii. And from that, their rotational inertia is effectively the same with respect to how they resist the efforts of a pedaler. That is, the 26in wheel is not "quicker" due to wheel size alone. (Maybe quicker by being lighter or by being geared differently/smaller than a 29er, but that's another question.)

    Thank you tbaier.

  121. #121
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    No problem. But one minor correction - mass doesn't have anything to do with it either. It cancels out also.

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    Quote Originally Posted by tbaier
    No problem. But one minor correction - mass doesn't have anything to do with it either. It cancels out also.

    Oh, ****. Now I'm less confident that the incline plane is a helpful test. No way am I going to get anywhere by arguing that not only does the wheel size not matter, but neither does the weight. That won't fly.

    Do you mean that the mass cancels because that is assumed constant between the two wheels under consideration, or do you mean that regardless of weight -- same OR different between two wheels -- they will descend the incline plan in a tie. Because they are both thin hoops, that is.

    If the latter, then this isn't getting us anywhere. Back to the drawing board . . .


  123. #123
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    im not the bright bulb on the tree or anything but i do know what fast is and what faster is. my 26" was fast. My new 29er is faster and much smoother. i can tell when im shooting down a mountain or even just coasting down a small trail or fire road. I dont know why its like that but it is. I love it and my 26" is now changed over to my work bike and the 29er is for blasting down trails here in southren Ca. I couldnt be more happy.

  124. #124
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    I want to return to rhis thread after my builds are finished wirh some comments. I hope I don't have any problem with toe overlap with my big feet! (size 14-15 depending on the shoe)
    roccowt.
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  125. #125
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    Quote Originally Posted by Li'l Bastard
    I sure 29ers roll a little better, but they aren't magic carpets, fer cryin' out loud.
    They are on this forum.

  126. #126
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    Bonking ... not feelin' well Sorry...

    Quote Originally Posted by 29erBidwell
    Do you mean that the mass cancels because that is assumed constant between the two wheels under consideration, or do you mean that regardless of weight -- same OR different between two wheels -- they will descend the incline plan in a tie. Because they are both thin hoops, that is.
    The latter is correct. Perhaps this web page will help:

    http://hyperphysics.phy-astr.gsu.edu/Hbase/hoocyl.html

    It compares a thin hoop and a solid cylinder rolling down an incline. The cylinder wins because of its lower moment of inertia, but that's not what is important here. Notice that in both of the formulas for velocity they have derived there is only gravitational field (g) and height (h) of the inline. (Go to the "Show More Detail" to see the derivation.) Nowhere is there mass or radius in the final product.

    Or in other words: "Dear 29ers, larger wheels are NOT INHERENTLY FASTER."

    Sorry if this hurts your mission.

  127. #127
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    26ers suck badly...
    http://mtobikes.com/are-29er%E2%80%9...he-big-wheels/
    "Kiddie wheels for kids only" an excellent motto for president campaign, don't you think?

  128. #128
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    Hope

    Hello, I'm gonna buy a 29er Steel HT soon and the few rides I've experienced leads me to these opinions,
    29's have stable forgiving handling,
    They roll over stuff better
    You don't feel like your gonna endo as easy
    I think Racers and Recreational riders like my self have great benefits in 29s.
    Can run some road and Cyclocross tires

    They are also slower in a drag race, all things equal,
    They are heavier all things being Equal
    Smaller Riders see fewer 29er Benefits,
    Larger Bikes can be harder to transport (ant got this problem my truck has an 8ft bed.)

    The allure of a 29er is certain to rally up the engineers and brain surgeons with power meters and calculators,

    Facts if your BMI is over 25 you are too heavy to be a great climber on any bicycle, the more time you ride the stronger rider you will become (if you dig your bike you will ride it to work, school, to the trail head, etc. The engine is you, the bike represents the rest of the drive train and chassis, the engine and the pilot (you) are the greatest factor in the level of performance and enjoyment you will get out of any bicycle.

    SF
    Who cares how much gas you save, ride your bike to work because it's fun!!!!!!!

  129. #129

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    Quote Originally Posted by Steel Freak
    The engine is you, the bike represents the rest of the drive train and chassis, the engine and the pilot (you) are the greatest factor in the level of performance and enjoyment you will get out of any bicycle.
    I was just about to post the same thing. Want to get an advantage? Ride more. Workout more. Eat right. No wheel size can substitute sweat and rest. HTFU!

  130. #130
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    Advantage enough to get rid of all my 26'er regardless of kind (AM, XC, Trail, HT, HL, TNT, FAux BAr, DW, Steel, and anything with little tiny 26" wheels).
    Sit and spin my ass...

  131. #131
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    Smile I ride to Smile:crazy:crazy:crazy:crazy:crazy:crazy

    Quote Originally Posted by Zion Rasta
    Advantage enough to get rid of all my 26'er regardless of kind (AM, XC, Trail, HT, HL, TNT, FAux BAr, DW, Steel, and anything with little tiny 26" wheels).
    My Ellsworth Moment may get sold if my 29er Project comes off as planned. The Ells is way too much bike for my riding style.

    The enjoyment factor is the biggest thing I go for in a bike. Stopwatches, lap times, mean nothing too me.
    SF
    Who cares how much gas you save, ride your bike to work because it's fun!!!!!!!

  132. #132
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    Quote Originally Posted by Steel Freak
    My Ellsworth Moment may get sold if my 29er Project comes off as planned.
    Get a comfy steel FS 29er, there are few of them.

  133. #133

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    is it not a fact that 29ers essentially are geared 1.5 time higher than 26ers? this fact has been mentioned in mbt mag and others.is a 29er faster downhill? yes I think so as they roll over terrain easier, inertia ect, on flats and climbing how could they be, I see no mention of physical effort required to get up to speed on a 29er

  134. #134

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    Quote Originally Posted by Fisty
    Go figure. I love passin 6ers on the fast downs. They never realize that we got more gear than them. I hammer right til I get to them and then stop pedalin just as I pass them. Things arent always as they seem.
    and you have more gear on the climbs and flats..about 1.5 higher gearing.

  135. #135
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    Quote Originally Posted by sexytime
    and climbing how could they be, I see no mention of physical effort required to get up to speed on a 29er
    Well check the tarmac and 650c vs 700c debate. 650c would be faster on smooth tarmac, really on perfectly smooth and steep climg the smaller thewheel the better a carbon 24" wouldwin or 20" as thre is no obstacles slowing you down.

    Now add mud, sand rolling stones and repeat the test assuming that you get the equivalent gears for a 29er.

  136. #136
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    Quote Originally Posted by dugodugo View Post
    Now guys...as Dave said, it's been refreshing to have a "civil" discourse, let's try to keep it that way. I think Dave's done some way cool testing. He's gone a lot further with what most folks here feel is the best way to get an answer (Cloxxki and his combustion engine aside).. . We all have opinions and that's exactly what they are...no matter how much testing is done.

    I myself am more in your camp Tbonius...I understand the physics, I see the test results and then I rode a 29er. Only once mind you and for less than 5mins. But it felt faster, it felt like it rolled smoother and I don't know if that's a psychological impact or whether something really is going on mechanically that is hard to quantify.

    I guess bottomline has been my question all along. If there were an advantage to a 29er, then NORBA and WC would have to penalize them when they ran with 26er's and Specialized and all the high end teams would be racing them. Since they haven't and aren't I can only assume they know something we don't or the jury is still out.

    I think the jury is still out!!!!

    Play on...play nice.
    That's exactly what I was thinking. Very interesting forum here. I like the physics discussion, and the points you guys are making...both sides. I agree there seems to be advantages and disadvantages. I think as someone mentioned above...it depends on the rider and the trail you are about to ride. Perhaps the best way is to have 2 bikes one 26er and one 29er. I can't help by think if you have a long climb up a road to a technical downhill, then maybe a 26er is better, but if on smooth rolling singletrack then maybe a 29er is better.

    I think if one had more of an advantage then you would see all the race teams on one type or the other.

    Will be testing out a 29er myself this weekend, as the switch....or maybe I should say option does sound intriguing.

  137. #137
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    I don't know if anybody has posted this link yet, but I think this is one of the best 26 vs 29 tests I've seen. The power meter, heart rate, and lap time differences are a very compelling argument for the 29er.

    http://singletrack.competitor.com/20...l-is-dead_3050

  138. #138
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    ...that test was flawed. Reading how he modified the riding to do the test, many rightly commented that the test method naturally favours the 29er.

    For a given weight and power, the system of rider and bike will always have a very similar average speed. The further you ride over the wider variety of terrain, the closer the averages will be. The only variables will be fatigue onset, how the bike suits a rider's natural ability, style and skill and the massive variable that makes off-road riding so much fun - the terrain.

    I like mountain bikes. I have both, I couldn't really care less about the wheel size as long as it's a good bike for the terrain and it's fun to ride. There's pros and cons of every variable on a bike including wheel size, make your choice and enjoy it. But saying one is simply 'better' than another like that test is taking personal taste and presenting it as a fact. Fact is, these pros and cons just aren't reliably measurable.

  139. #139
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    its clear that it depends on the rider who makes the bike faster. If you put a 29er and 26" mtn bike side by side with riders of equal size and just coast (no pedaling) down a road the 29 pulls away. Just my 2 cents. At the end of rides in Chessboro Ca, we would coast down the to the cars together and i would always pull away from the group.

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    You can check out a review from this season by a woman in Whistler on the Muddbunnies website.

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    I tested several 29ers and settled on a 2011 Specialized StumpJumper Comp 29er hard tail. It weighs 5-7 pounds less than the $2500-3500 full suspension aluminum bikes that I demoed. It climbs really well and the 29's smooth things out nicely compared to my 26 hard tails, with and without XC tires. It would be better on rocky trails with more aggressive trail tires.

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  145. #145
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    Does not this thread fall under the moratorium?

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    DC must not have taken his time out too seriously.

  147. #147
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    Quote Originally Posted by AZ.MTNS View Post
    DC must not have taken his time out too seriously.
    Most apparently.

  148. #148

  149. #149
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    The most interesting part of this 6 year old thread was seeing how UCI World Cup XC races went from a field of one 29er to a field of probably one 26er (which coincidentally happened to win the last race).. and now some 650b's too...

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    Assuming we're talking all mountain, it still depends to some extent who you are - someone 5'4" and nine stone, who handles a 26er with real skill, possibly not. A six foot four heavyweight, with not so much technical skill, who wants to fly down firetrail fast, and prefers a more comfortable ride, possibly yes. Apples and oranges. Riding a bike one likes, regardless of wheel size, is far more of an advantage, but there's no doubt 29er is the latest thing to be aggressively marketed by a profit driven industry.

  151. #151
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    I don't know about that. I own both and the 29er definitely moves me down the trail faster but I have more fun on the 26 so it gets ridden more. I'm 6'1". I do agree with your last statement. There is always something the marketers try to rally around to convince us we need the latest and greatest.

  152. #152
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    It depends on the trail. Tight tech= 26. Flow=29.

    As far as efficiency goes tho.... E=MC2

    Several "test' or comparisons have shown that physics is still universal.
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  153. #153
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    While entertaining and informative at times, it can also be annoying like watching kids fight for the same bucket in a sand box shrieking like immature spoiled kids whose mommy always tells them they're the best at everything (despite the opposite), this whole 26 v. 29er thing.

    Lest y'alls forget that the entire UCI XCO field (save Nino's 650b rig of late) rides 29ers. They are in it to win it. Speed is their first priority. They ride 29ers. They forgo feel, response, cornering, climbing, etc in favor of speed. There must be something to 29ers if 99.9% of UCI XCO rides them. I trust what professional racers ride over what forum monkeys spew forth.

    Stop Monkeying Around

    On, carry.

  154. #154
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    Quote Originally Posted by 6bobby9 View Post
    It depends on the trail. Tight tech= 26. Flow=29.
    That is a good way to think about it and fits my experience.

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    Quote Originally Posted by FX4 View Post
    I don't know about that. I own both and the 29er definitely moves me down the trail faster but I have more fun on the 26 so it gets ridden more. I'm 6'1". I do agree with your last statement. There is always something the marketers try to rally around to convince us we need the latest and greatest.
    Sounds familiar. I own two 29ers....an 18 inch and 19 inch. The 18 comes closer to 26ers on the trail....for me. I would seriously recommend trying a size smaller than you ride in a 26. Keep that in mind when talking to bike salespersons who may not understand that dynamic on trails.

  156. #156
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    Quote Originally Posted by sumgai View Post
    Lest y'alls forget that the entire UCI XCO field (save Nino's 650b rig of late) rides 29ers. They are in it to win it. .
    What does riding in a XC World Cup have to do with trail riding needs of 99.99% of the mountain bikers?

    Nothing.

    If anything, DH series are more interesting.

    In any case - out of 5 WC stages in 2012, #1, #3 and #5 won on 650b and #4 on 26" (Absalon). So who is there to win it?

  157. #157
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    Whoa! I thought the OP was trolling, but this all started in 2006 back when asking these questions were somewhat valid

    To answer the OP... "yes". Riding a 29er will change everything. Even your taxes will disappear. You will get a raise and marry a supermodel most likely. I mean...odds are..

  158. #158
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    New question here.

    Quote Originally Posted by sumgai View Post
    While entertaining and informative at times, it can also be annoying like watching kids fight for the same bucket in a sand box shrieking like immature spoiled kids whose mommy always tells them they're the best at everything (despite the opposite), this whole 26 v. 29er thing.

    Lest y'alls forget that the entire UCI XCO field (save Nino's 650b rig of late) rides 29ers. They are in it to win it. Speed is their first priority. They ride 29ers. They forgo feel, response, cornering, climbing, etc in favor of speed. There must be something to 29ers if 99.9% of UCI XCO rides them. I trust what professional racers ride over what forum monkeys spew forth.

    Stop Monkeying Around

    On, carry.
    and the win in Le Bresse? the race right before Mont Sainte Anne... who won that and what size wheel was he riding on? I forgot....

  159. #159
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    I feel the advantage of a 29er is completely valid..especially in SingleSpeed where inertia, flow, efficiency, and moment is most critical.

    Who here is faster on a 26" SS than a 29" SS? Just curious..

    I don't think weight is as much of a factor...if you look at offerings from American Classic.
    1419g 29er wheelset, and 1321g for 26"...a 50g difference per wheel...with rubber not so much of a difference. Of course these are race wheels and not the norm for the "99.9%" but trickle down technology has become more affordable. I suspect that the weights across the line for 26" and 29" to follow similar differences.
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  160. #160
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    29er's have absolutely NO advantages, espically if your an xc racer! Better stay on a 26 if you wanna win!




    (Hopefully my competitors will stay on 26s, hehehe)

  161. #161
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    My wang grew 4" after starting to ride my 29er.
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  162. #162
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    Its not the bike, its the rider! If I am still riding at 70 years old, I don't care what the bike is, at least I am still ridin'! I love how the bike industry is bringing all these sizes up to boost sales of all the impulse purchases from riders that make impulse purchases every year. Here's a thought, lower the pricepoint so more people will ride and more trails can be built!

  163. #163
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    ^ spam reported
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  164. #164
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    What's with bringing back all these old threads for no good reason?
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  165. #165
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    Quote Originally Posted by Simpledesign View Post
    What's with bringing back all these old threads for no good reason?
    New users learning to use the search function.

  166. #166
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    Quote Originally Posted by sumgai View Post
    While entertaining and informative at times, it can also be annoying like watching kids fight for the same bucket in a sand box shrieking like immature spoiled kids whose mommy always tells them they're the best at everything (despite the opposite), this whole 26 v. 29er thing.

    Lest y'alls forget that the entire UCI XCO field (save Nino's 650b rig of late) rides 29ers. They are in it to win it. Speed is their first priority. They ride 29ers. They forgo feel, response, cornering, climbing, etc in favor of speed. There must be something to 29ers if 99.9% of UCI XCO rides them. I trust what professional racers ride over what forum monkeys spew forth.

    Stop Monkeying Around

    On, carry.
    Actually most riders at that level are sponsored so they ride why their sponsors make! Who still makes top level XC 26ers? Not many of the big brands that's for sure.

  167. #167
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    Quote Originally Posted by Ruscopybook View Post
    Скачать учебники ГДЗ - 5 6 7 8 9 10 11 класс Скачать учебники, ГДЗ класс: 5, 6, 7, 8, 9, 10, 11 для школы бесплатно ruscopybook com/mathematics/]учебники по математике
    I couldn't agree more. I think this is by far the most compelling argument for 29ers since 2006 when this thread started. I sure wish we could resurrect all the threads that date before 2006 so they can have spam added to them as well. I think its really special.
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    If I told you I saw a unicorn ****ing a leprechaun trail side, you'd probably be suspicious. :D

  168. #168
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    Quote Originally Posted by PeopleForScience View Post
    I couldn't agree more. I think this is by far the most compelling argument for 29ers since 2006 when this thread started. I sure wish we could resurrect all the threads that date before 2006 so they can have spam added to them as well. I think its really special.
    Do not quote spammers. Let mods clean it up.

  169. #169
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    More riders accustomed to 29er, and yes 29er has it's advantage.

  170. #170
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    Quote Originally Posted by TiGeo View Post
    My wang grew 4" after starting to ride my 29er.
    No thanks! A 16" wang would be way too cumbersome.

  171. #171
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    New to 29er this year

    And after 20 rides or so, my observations are 29er is faster over the semi-technical XC terrain I ride. I think the ability to keep the wheels rolling over the rocks and roots helps keep momentum up. Where the 26er excels is tight twisty stuff. Much more work navigating the 29er through a tight rocky climb, or basically anything at slow speed. But the 29er is more fun. Oddly, my cranks seem to have grown on the 29er, as it seems far more likely to bottom out than my 26er. The bb's seem to be the same height or within a 1/4 inch difference at most. I am guessing this has something to do with the longer wheelbase or the fact that I can roll over larger objects on the 29er (not a hoax, this is the most noticeable aspect to me).

  172. #172
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    Cool video on Pinkbike: Opinion: 26 vs 27.5 vs 29-inch Wheels - Pinkbike

    Even cooler is the stable of Heliuses they use for testing. Now that is a proper way to compare - custom geometry on each size to set it up just right for each size. Having a 26" Helius AM - that's a great builder and frame to use.

    Seems everybody (admittedly it is Pinkbike) felt they roll faster on 29", but had more fun on smaller wheels. Whatever they think, it is a cool way to compare - I wish I had all three Heliuses for different days of the week.

    For what it worth, I decided against setting mine up with 650b (I could pretty much replicate their 650b geometry with adjusting shock mount, and limiting travel on both ends to 160mm)

    Decided that 170mm and 26", (with Lyrik Coil DH now, and CCDB air) is more fun. I will keep larger wheels for shorter travel bikes when I get them.

  173. #173
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    I have two xc bikes, one is 29 and the other is of course 26
    I love them both!!
    I just grab the closest bike to me and go ride.
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  174. #174
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    The most notable difference for me in making the change from 26 to 29 has been that I don't get nearly as beat up when riding the trails. I perceived myself to be faster, but when I compared times on the same trails between the two bikes, they were almost identical. I do think that when I fully figure out how to exploit the advantages of the 9'er, I will be. I am an old man with bad joints, and my joints can really tell the difference, so this alone makes the switch worth every penny.

  175. #175
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    Thread revival

    Okay here is my real question and its more towards climbing. Consider bikes, a 26er and a 29er both exact same weight same rider. Wheels also same weight. Both granny gear the same with 24x34. The 26ers gear inch of travel is 18.31 inches, the 29ers is 20.23.

    So basically the 29er goes 2 inches farther per crank.

    But this extra 2" of gain requires a more work on the part of the rider.
    The amount of extra work depends on two things at this point, incline slope and momentum.

    on a flat this is negligible, and on a slope already moving is somewhat negligible, But after many miles on a steep incline moving at 2-3mph. this power difference can be the difference between riding as on the 26er and getting of the 29er and walking.

    Agree?

  176. #176
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    Quote Originally Posted by barrelquest View Post
    Consider bikes, a 26er and a 29er both exact same weight same rider.
    Why would they be the same weight? Considering you can build a stronger wheelset in smaller size, 26r that is about as strong should be a pound or two lighter.

    And they certainly should not be geared the same, you match gear inches, not gear ratios.

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