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  1. #5651
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    Quote Originally Posted by meltingfeather View Post
    "Sounds plausible" is armchair quarterbacking.
    What you find when you actually do it and measure it (reality) is that bead seating causes the drop. Pressure does virtually nothing.
    There is a thread posted here that I started on this very topic with measurements and figures.
    Bead seating? Did you do FMA on it? Interesting. Yeah, I was just guessing.

    Just about the forces involved, 60 psi about 400000 N m2. 0.03m width, 0.580*3.14 = 1.8m, 0.0546m2 inner rim surface, 22612 Newton of force. 2 tons inwards. Is it right?

  2. #5652
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    Quote Originally Posted by David C View Post
    TTurns out they shipped me 252mm spokes, while I needed 250's, 251's and 253's.
    That should about work, should not it? Maybe with one of those nipples with longer threading. Dont many brands only come in even mm sizes anyway.

    I think local shop I use have a cutting machine, will ask what they will do. Did you measure ERD by any chance yourself? I see different numbers in this thread, maybe different rims (was thinking on 29 hookless). I guess I can ski the spokes.

  3. #5653
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by Axe View Post
    Bead seating? Did you do FMA on it? Interesting. Yeah, I was just guessing.
    If you mean FEA, no... I took actual measurements.
    Measure tension, seat tire, measure again, start adding pressure, measure every 5 psi. Do the same thing on the way back down, all the way to unseating the bead.
    Quote Originally Posted by Axe View Post
    Just about the forces involved, 60 psi about 400000 N m2. 0.03m width, 0.580*3.14 = 1.8m, 0.0546m2 inner rim surface, 22612 Newton of force. 2 tons inwards. Is it right?
    Don't know... I answered my questions with measurements. Theoretical stabbings (armchair quarterbacking) are a waste of time when 30 minutes with a pump and a tensiometer will make sure everything is covered.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  4. #5654
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    Quote Originally Posted by meltingfeather View Post
    Don't know... I answered my questions with measurements. Theoretical stabbings (armchair quarterbacking) are a waste of time when 30 minutes with a pump and a tensiometer will make sure everything is covered.
    Tensiometer is the end result. Forces involved can a) deform rim cross section shape pushing beads apart. b) compress rim inwards with the force I calculated above. Is there an option c)? Which one is the main cause - I had no idea. Not that it is that important.

    Armchair quarterbacking is what we do on da webz.

  5. #5655
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    Quote Originally Posted by Axe View Post
    Tensiometer is the end result.
    Exactly. The beauty of it is that it actual measurements catch all the things you forgot to account for.
    Quote Originally Posted by Axe View Post
    Armchair quarterbacking is what we do on da webz.
    What my thread did "on da webz" was report measured data.
    Keep speculating about what forces might be involved and what dynamics might be affecting the tension, etc... I know already because I have a pump and a TM-1
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  6. #5656
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    Quote Originally Posted by Axe View Post
    That should about work, should not it? Maybe with one of those nipples with longer threading. Dont many brands only come in even mm sizes anyway.

    I think local shop I use have a cutting machine, will ask what they will do. Did you measure ERD by any chance yourself? I see different numbers in this thread, maybe different rims (was thinking on 29 hookless). I guess I can ski the spokes.
    Unfortunately, no. They were too short except for the front disc side. I think they were actually 251.5mm. Anyway, I tried them at first and they were too short for real. These were the 26 DH rims, ERD was spot on. The Pillar spokes are awesome, I almost want to order them back, since I know the exact lengths now, but it's not worth it to relace the wheels just because of that anymore.
    Quote Originally Posted by NicoleB28 View Post
    topless. that's what all mtb girls do. we go ride, get topless, have pillow fights in the woods, scissor, then ride home!

  7. #5657
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by David C View Post
    Lol, I'd easily imagine you spending over an hour trying to fish in a single nipple, since obviously you have no clues on what you're talking about.

    3 minutes top is what it'll take you if the nipple to be replaced is the one further away from the valve hole. 30 seconds or less for the 6~8 closest nipples and between a minute or two for all the others. The only difference would be not having to redo your rim tape setup or in the case of using the gorilla tape with an old inner tube valve, you wouldn't have to also retape the valve. In both cases, you'd still need to pluck the valve out anyway, unless your setup has the valve independent from the tape.

    In the end, it's only gonna take you 3 minutes more to do the job if you have undrilled vs drilled. You'll still have to take the tire off, clean the sealant, take the tape/valve out, shake the old nipple out of there, get the new lube nipple in, etc. No big deal.
    I am guessing you have never tried to get a nipple out of the rim bed before.


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  8. #5658
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    Quote Originally Posted by MTBMILES View Post
    I am guessing you have never tried to get a nipple out of the rim bed before.


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    Well you guessed wrong about 120 times. Better luck next time !
    Quote Originally Posted by NicoleB28 View Post
    topless. that's what all mtb girls do. we go ride, get topless, have pillow fights in the woods, scissor, then ride home!

  9. #5659
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    ok enough.

    can you take this elsewhere? put it in another thread. call it the "Undrilled Rim bed thread". In there, you can have how to's, and continue your debate on the merits of it. in that thread, you can say "if you don't like it, get out of this thread".

    but stop making a meal of this thread.

    i am sick of hearing about you trying to make out that this undrilled rim bed approach to be the be all and end all. play down the downsides, and drum up the upsides. there are plenty of people on here that have had the competency to apply some rim tape to a rim and have it not leak. you trying to sell the idea to the people that can't seem to get this right is absolutely ridiculous - if they can't put some tape on a rim, how do you think they'll go fishing nipples through a rim?

    likewise, the detractors. if you be quiet, maybe he will go away. let him have his little peace of mind that the rim tape is not gonna leak, and that he saved 2 grams per wheel. no need to be so negative, when someone obviously needs to have this, so don't try to take it away.

  10. #5660
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by meltingfeather View Post
    What my thread did "on da webz" was report measured data.
    Keep speculating about what forces might be involved and what dynamics might be affecting the tension, etc... I know already because I have a pump and a TM-1
    Good for you, and thank you for sharing your data. Some of us also enjoy understanding of underlying causes, even if it is "speculation" and discussion. I see nothing wrong with that.

  11. #5661
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    Lol, sclyde2, get lost. Some people here started asking me about undrilled rim bed, so I answered their questions. Others came in saying it's not worth crap and we debated about the pros and cons. Im not saying this is the only way to go, simply offering advises on how to do it for the ones who are interested in it. Sone other people (not pointing any fingers here) jumped in and started trolling the conversation about undrilled rim bed. Anyway, I think everything has been said, so I'm done for this. Move on to the ride reports of hookless rims. These are very interesting none of the less.
    Quote Originally Posted by NicoleB28 View Post
    topless. that's what all mtb girls do. we go ride, get topless, have pillow fights in the woods, scissor, then ride home!

  12. #5662
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    Quote Originally Posted by meltingfeather View Post
    It's not the pressure it's the bead seating tightly.
    I disagree with this claim. The bead is not shrinking in diameter as it seats; if anything, it is stretching (albeit ever so slightly). The air pressure, on the other hand, is literally a force pressing in direct opposition to the spoke tension, so it unsurprisingly reduces the measured tension.

    If you need proof of this, try the following experiment: A road tire works best since it has a wider range of pressure. Install a tire. Add enough pressure to seat the bead. Then raise pressure to the highest practical (100-120 psi in many road tires); measure the spoke tension. Now reduce the pressure to 10-20 psi; measure the spoke tension again; although the bead remains tightly seated, the tension will be noticeably lower.

    Spoke tension reducing as tire pressure increases is a normal phenomenon, although I'll concede it is UNcommon for folks to observe it.

    I've often read that "appropriate" spoke tension is in the 80-120kgF range, but I've never found anyone citing whether that ideal tension is measured with, or without, a tires installed. Given the other post about losing 30kgF in an extreme example (noodly rim with high tire pressure) it seems to me that this would be a useful clarification.

  13. #5663
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    Quote Originally Posted by David C View Post
    Anyway, I think everything has been said, so I'm done for this. Move on to the ride reports of hookless rims. These are very interesting none of the less.
    nice

  14. #5664
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by David C View Post
    Well you guessed wrong about 120 times. Better luck next time !
    It took you 120 tries to get the nipple out, so sorry for you.


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    Quote Originally Posted by MTBMILES View Post
    It took you 120 tries to get the nipple out, so sorry for you.
    stop it. could we try not to stir it up.

  16. #5666
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by sclyde2 View Post
    stop it. could we try not to stir it up.
    Okay, I apologize. I have had great luck running the hookless rims by Derby, and running low-pressure 17 pounds and have had no burps or pressure loss. I have been using the Chunky Monkeys.


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  17. #5667
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    Quote Originally Posted by MTBMILES View Post
    Okay, I apologize. I have had great luck running the hookless rims by Derby, and running low-pressure 17 pounds and have had no burps are pressure loss.
    wow 17 pounds. how light are you? what tires were those?

  18. #5668
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    (Cheap) Chinese Carbon Rims?

    I am 160lbs and I have the 2.4 in the front. I have struggled to get spoke nipples out of deep dish road wheels, so I know it can be difficult.


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  19. #5669
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    Why all the hate for David C for mentioning a viable option to build with no-bed-hole rims? He didn't say everyone using tape were idiots. I perceived his "arguments" to be just a list of his personal rationales for making the effort, not an attempt to establish his approach as superior for all.

    Both approaches are valid. Some of the arguments for not using tape are admittedly pretty ridiculous (weight savings? as has been noted, yellow tape probably weighs about as much as the carbon being drilled, maybe 2g more).

    For me, the attraction of having no tape is really just an elegant touch with some minor practical benefits (no tape hassles, however modest they may be) and some significant downsides (much more tedious wheel build).

    For those that want to trade tedium and time for that bit of elegance, feel free. For those that don't, that's great too. But this dogmatic, polarizing and hateful ranting seems ridiculous in the context of what should be just another interesting wheel building option.

  20. #5670
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    Quote Originally Posted by meltingfeather View Post
    "Sounds plausible" is armchair quarterbacking.
    What you find when you actually do it and measure it (reality) is that bead seating causes the drop. Pressure does virtually nothing.
    There is a thread posted here that I started on this very topic with measurements and figures.
    Coincidentally, I did this very measurement on three wheels and found the exact opposite conclusion that you did. I found a consistent and measureable reduction in tension as tire pressure reduced, up to the point at which the bead "relaxed," and there was no additional de-tensioning after the bead relaxed.

    I found your other thread on this topic, and noticed is was primarily about a Crest rim, which may explain some of the difference in our observations. In my case, all the wheels were "normal" road rims with typical beads, 450-500g/rim, 28-32H such as Open Pro, RR1.1, and Synergy.

    Probably best to continue the discussion in the other thread, if you want, but I thought I'd note this here since the conclusion, in my opinion, isn't so black and white.

  21. #5671
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    Quote Originally Posted by InertiaMan View Post
    Coincidentally, I did this very measurement on three wheels and found the exact opposite conclusion that you did. I found a consistent and measureable reduction in tension as tire pressure reduced, up to the point at which the bead "relaxed," and there was no additional de-tensioning after the bead relaxed.

    I found your other thread on this topic, and noticed is was primarily about a Crest rim, which may explain some of the difference in our observations. In my case, all the wheels were "normal" road rims with typical beads, 450-500g/rim, 28-32H such as Open Pro, RR1.1, and Synergy.

    Probably best to continue the discussion in the other thread, if you want, but I thought I'd note this here since the conclusion, in my opinion, isn't so black and white.
    I have found this to be the more true explanation also. The bead with no air makes a small difference, but as you increase the pressure the spoke tension tends to lessen.
    Full rigid SS, Hardtail SS, Hardtail Geared, Full Suspension Geared.

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    Quote Originally Posted by sclyde2 View Post
    Yeah, what he said. People have found this with notubes rims especially with tight fitting schwalbes.

    The drop in tension most likely happened when you put the tire on, before you aired it up. To confirm, try measuring the tension with the tire flat.

    Dunno where they get the 40psi max from. The LB site says 70psi - but I wouldn't go trying to do that with a 2.35 tire. I'm running my 27mm rims with 35mm touring tires at 60psi on my commuter.
    Good to know there are others using this rim incorrect.
    That roval rim blowup was still thing to keep in mind
    32mm tyre on 27mm rim is slightly, may i say erotic looking combo

    edit: your 60psi is sick. now ridden these wheels and they are solid rock.
    60psi you have to be 110kg weight, steel frame or at least front suspension.
    me, aluminum frame, 80kg i went to 30-35psi . so much vibrations.
    tyres are challenge strada biancas now and rode those mavic a719 rims about 40-45psi

    My second tubular wheels i ride 40-50psi.

    shieett these are stiff

    Last edited by manninen; 04-04-2014 at 10:03 AM. Reason: pressure

  23. #5673
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    You are totally right...343 and 362..I was calculating the weight difference vs my Arch EX, and somehow got the "4" in my head.

    Quote Originally Posted by TheKaiser View Post
    Gabe, are those the actual weights, or did you type a "4" accidentally rather than a "3"? If those are actual weights, are you sure you got regular 27mm hookless and not 35mm? If they are indeed 27mm (external), did you request an extra strong or DH build with additional carbon plies?

    I ask because just a few posts up from yours Manninen stated "Just received my 27mm hookless and weights are 339 and 349.". Also, Lightbicycle quotes 365 for that rim. The mid 400s is where several people are reporting their 35mm rims coming in.

  24. #5674
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by InertiaMan View Post
    Coincidentally, I did this very measurement on three wheels and found the exact opposite conclusion that you did. I found a consistent and measureable reduction in tension as tire pressure reduced, up to the point at which the bead "relaxed," and there was no additional de-tensioning after the bead relaxed.

    I found your other thread on this topic, and noticed is was primarily about a Crest rim, which may explain some of the difference in our observations. In my case, all the wheels were "normal" road rims with typical beads, 450-500g/rim, 28-32H such as Open Pro, RR1.1, and Synergy.

    Probably best to continue the discussion in the other thread, if you want, but I thought I'd note this here since the conclusion, in my opinion, isn't so black and white.
    This is interesting.
    There are many variables, one of them being whether the tire stays seated as it is deflated and another being how tight the interference fit between rim and tire is.
    Maybe a carbon rim is more susceptible to pressure effects on spoke tension than a Crest. I wouldn't have thought so, but I'll do the same experiment on my Nancy Wides.
    For those of you who have done this or say you have, post up your measurements in the other thread.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  25. #5675
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by InertiaMan View Post
    But this dogmatic, polarizing and hateful ranting seems ridiculous in the context of what should be just another interesting wheel building option.
    Melodrama isn't helpful or interesting.
    Maybe you haven't been around enough or not in the right threads to know David C. is a respected contributor many of us have dialogued with quite a bit. It's not hate, you just don't get it.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  26. #5676
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    Quote Originally Posted by meltingfeather View Post
    This is interesting.
    There are many variables, one of them being whether the tire stays seated as it is deflated and another being how tight the interference fit between rim and tire is.
    This.

    I measured a 20% spoke tension drop bead seated vs unseated (no air pressure) on both a Crest/Maxxis Ardent and Crest/Schwalbe Nobby Nic, but a different rim design and a less tight tire/rim interface might give different results.

    For me, it is a fact that if the tire/rim interface is tight and a tire bead is very resistant to stretch, this can produce a significant spoke tension drop. There might be other factors that produce such a drop; I don't know.

    @IntertiaMan, there is a big difference between the road rims you describe and both Notubes and LB rim designs. The MTB designs have a flat portion of the rim bed on which most tires have a tight fit. This is where the pressure comes from. Most road rims do not have this. With such a design, a road tire bead only puts side pressure on the rim wall, no downward pressure on the rim bed.

  27. #5677
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    Quote Originally Posted by David C View Post
    Uncut fiber is stronger than perforated fiber. Pretty basic science right here.

    However, it wouldn't make much of a difference since the fiber being perforated in this case isn't the one dealing with much of the rim strength. So it's negligible. Using internal nipples does make the rim stronger as the nipple hole is only 2~3mm Ý vs regular nipples that requires a 4~5mm Ý hole. The internal nipples also distribute their load on a larger area than the standard nipples would, making the overall rim stronger and more durable. Cons are no wheel tuning with tires on and you can go undrilled, but pros are a stronger wheel and less chance to round off a nipple and a cleaner look.

    So many ways to enjoy your new wheels
    No clue, eh? Well I guess I have no clue of how to build wheels, considering I only have maybe built 12 of my own wheels with no failures multiple years out. Okay, one failure when I tried to turn to sharp at the bottom of a flight of stairs, and I folded the rim over. Wups. Not that I would build rims professionally for anybody else. It takes me a couple hours to lace up, tension and true a wheel. The pros knock it out in 30 minutes and do a good job with it. That said, I think my results are pretty dang good, if I do say so myself. I get very even spoke tension all the way around with no hops or waves. BTW, I haven't had to touch my LB carbon/Hugi/Lefty wheelset since I built it a year and a half ago, and I abuse these things like a rental car under my 210 pound fatass. Still straight as flock.

    So, maybe I don't have a clue. Please, fill me in. I would love to learn as long as you aren't a d!** about it.

    My point was more that nipples fail way more often than spokes, as long as you use good quality spokes of the appropriate type for the job at hand. Seems like a lot of work to sole a non-problem.... seems like they want to milk the cow by lifting all 4 legs up and down.

    So, for my own education, how do you fish a nipple through a no-hole tire bed rim without using Mavic style reverse thread installed nipples, that require a larger hole and are more prone to fail, or cause damage to the rim when it does fail in the first place? Heh... not that I would ever do that. I don't run tubeless anymore (no advantage in my case, but more extra work, and potential repair time eating into my ride time), anyway, but if I did I would rather re-tape the rim.

    Plain-Jane setup of 32 double butted DT Swiss spokes with brass nipples has always been a super reliable setup for me, with only a 15-20g weight penalty over alloy nipples. Honestly I don't have a lot of motivation to change things. I have zero desire to impress my friends with slick sounding, but useless whiz-bang pseudo-"upgrades". I just want my stuff to work reliably and perform well.

    As far as saving the weight of a rims strip goes, I'll bet the metal left in the rim from not drilling weighs more than a lap of Stan's Rim tape.

    *edit*

    Weird. The message board just switched the original quote to a different quote.

  28. #5678
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    Quote Originally Posted by JeroenK View Post
    @IntertiaMan, there is a big difference between the road rims you describe and both Notubes and LB rim designs. The MTB designs have a flat portion of the rim bed on which most tires have a tight fit. This is where the pressure comes from. Most road rims do not have this. With such a design, a road tire bead only puts side pressure on the rim wall, no downward pressure on the rim bed.
    I'm fully aware of this difference, which is why I noted the specific rims I had run this little experiment on many months ago. That doesn't negate the fact that my measurements are directly contradictory to some folks claiming that "tire pressure has no effect on spoke tension." I contend that it does have a significant and measureable effect. I'm speculating that it has an effect regardless of rim design, and I'll do some additional measurements to test that theory & post them later.
    In parallel, I'll still happily listen to evidence that the tire bead / rim combo may also contribute to de-tension, and if/when it does, I'd certainly expect the scale of that effect to be dependent on the rim/tire designs.

  29. #5679
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    Quote Originally Posted by manninen View Post
    Good to know there are others using this rim incorrect.
    That roval rim blowup was still thing to keep in mind
    32mm tyre on 27mm rim is slightly, may i say erotic looking combo

    edit: your 60psi is sick. now ridden these wheels and they are solid rock.
    60psi you have to be 110kg weight, steel frame or at least front suspension.
    me, aluminum frame, 80kg i went to 30-35psi . so much vibrations.
    tyres are challenge strada biancas now and rode those mavic a719 rims about 40-45psi

    My second tubular wheels i ride 40-50psi.

    shieett these are stiff

    Oooh, sew-ups! I've always wanted to go with tubulars on my cross bike. I really don't ride that bike enough to justify putting bling anything or spending real money on her.

  30. #5680
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    Tire pressure vs. spoke tension data posted on other thread

    If anyone cares to review it, I posted a fresh set of data here:

    Tire Pressure and Spoke Tension

    Short summary:
    Tire pressure meaningfully reduces spoke tension on all wheels.
    Bead seating meaningfully reduces spoke tension on tire/rim combos intended for tight seating, aka tubeless, and it contributes proportionally more in tighter rim/tire combos.
    In the case of this thread (carbon MTB wheels typically run tubeless at 25-ish PSI) the two factors contribute in roughly comparable proportion, though the bead seating might be as high as a 70% contributor to de-tensioning in particular cases (tight bead, low pressure).

  31. #5681
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    Quote Originally Posted by InertiaMan View Post
    If anyone cares to review it, I posted a fresh set of data here:

    Short summary:
    Tire pressure meaningfully reduces spoke tension on all wheels.
    Bead seating meaningfully reduces spoke tension on tire/rim combos intended for tight seating, aka tubeless, and it contributes proportionally more in tighter rim/tire combos.
    In the case of this thread (carbon MTB wheels typically run tubeless at 25-ish PSI) the two factors contribute in roughly comparable proportion, though the bead seating might be as high as a 70% contributor to de-tensioning in particular cases (tight bead, low pressure).
    Is not it the main idea of Stan's rim profile that it has a non-standard (larger diameter) bead seat combined with a lower than normal hook, so as to work better with a non-tubeless bead. So placing a bead on applies pressure to the bead seat. That is also the reason I do not like to use Stan's anymore, especially with EX iteration, no need to apply such tricks as modern tubeless compatible tires seat well anyway (like on ~UST shaped WTB rims).

  32. #5682
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    Quote Originally Posted by InertiaMan View Post
    I'm fully aware of this difference, which is why I noted the specific rims I had run this little experiment on many months ago. That doesn't negate the fact that my measurements are directly contradictory to some folks claiming that "tire pressure has no effect on spoke tension."
    You're right, it does not. I did not read your post well enough (non native English speaker here...) and mistakenly concluded you were not aware of the design differences.

  33. #5683
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    Re: (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by TedS123 View Post
    Just got a note from LB saying my rims are done. I ordered the AM weight 27 mm wide hookless. They are reporting weights of 351 & 360. I've replied asking to confirm that these are AM weights, but maybe they are coming in under the listed weights for both XC and AM.

    Sent from my XT907 using Tapatalk
    Heard back from LB: 351 & 360 were for XC weight rims. They then offered AM weight rims at 399 & 431 ready to ship. The whole order and communication process is going smoothly thru eBay. Just waiting for a tracking number...

    Sent from my XT907 using Tapatalk

  34. #5684
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    Kappius Rims

    I just posted info on wheels/tires but thought it should also be posted here since the originator of this thread (how many years ago?) is rkappius.
    Apparently he has been working on this for awhile!
    (Cheap) Chinese Carbon Rims?-kappius-carbon-rim-dimensions.jpg
    I would love to have a set of these laced up to their KH-1 hubs, dream wheelset! It says they are available 2014 as rims and wheelsets. Thomas Dooley and Mike Hogan rode these at Cape Epic last week with no problems.

  35. #5685
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    Andy, those ^ specs for the Kappius rims are pretty damn impressive! Thanks for posting this. Any idea on how they distribute these? ie. consumer direct, or through shops?

  36. #5686
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    So after much deliberation, I have just ordered the rims only, Wider carbon mountain 29er rims clincher(tubeless-compatible)...I just hope they live up to my expectations.

    At least they are cheaper than Enves and hopefully better than the Specialized Rovals..

    I plan to have them built in DT Swiss 240 hubs and Sapim CX-Ray spokes...

    Does anyone know what the appx delivery dates to the UK on these babies ??

  37. #5687
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by ritchief View Post
    I plan to have them built in DT Swiss 240 hubs and Sapim CX-Ray spokes...
    What nipples?

  38. #5688
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    I think that they will be Sapim Secure Lock, but I am waiting for the wheel builder to confirm.

  39. #5689
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    I always think better while I'm riding...... I thought I might have ruffled some feathers w/ my post about Kappius rims/wheels. I realized while riding today that they're not that cheap and they are sold by an american company, although they are made in China to Kappius specs. As far as I know they sell only consumer direct due to them being such a small company. They may be available through shops, but I don't know. The rims will be available (per the website) soon for $599 each. Less than Enve but much more than LB. The rims, along w/ the hubs, are definitely a high end product. Like I said, I posted mostly because my belief is that rkappius who started this thread is Russ Kappius of Kappius components.

  40. #5690
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    Here is my latest setup. Wider 29er rims 30ID, CK hubs, DT straight guage spokes, long brass nipples.


  41. #5691
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by mudpuppy View Post
    Here is my latest setup. Wider 29er rims 30ID, CK hubs, DT straight guage spokes, long brass nipples.

    ]
    What type of riding do you intend for this build?

  42. #5692
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    AM. I live in BC and ride everything, it may even see a park day or two.

  43. #5693
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    Very cool wheelset!
    Quote Originally Posted by mudpuppy View Post
    Here is my latest setup. Wider 29er rims 30ID, CK hubs, DT straight guage spokes, long brass nipples.


  44. #5694
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    (Cheap) Chinese Carbon Rims?

    Quote Originally Posted by mudpuppy View Post
    Here is my latest setup. Wider 29er rims 30ID, CK hubs, DT straight guage spokes, long brass nipples.

    Are there advantages to long vs regular nipples?

  45. #5695
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    Current Thinking on Tubeless?

    Early on in the thread, it seems like there was a great deal of success in using the Bontrager rim strips for easy tubless conversion. However, that seems to have been primarily with what they now call their XC rim.

    Some later posts related to the wider AM rim indicate that using the Bontrager strips might not be so straight-forward. It seems some of these were using Stans valves instead of the Bontrager valves. I don't know if that's a contributor of if the Bontrager valves don't work at all.

    Then there have been posts about using Stans, Gorilla tape, etc.

    I've ordered a set of the AM 29er rims and was planning to use the Bontrager strips and valves (and sealant) for my setup. But wanted to see if anyone wanted to summarize the current thinking on going tubeless with the AM rims.

  46. #5696
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    Quote Originally Posted by objectuser View Post
    Early on in the thread, it seems like there was a great deal of success in using the Bontrager rim strips for easy tubless conversion. However, that seems to have been primarily with what they now call their XC rim.

    Some later posts related to the wider AM rim indicate that using the Bontrager strips might not be so straight-forward. It seems some of these were using Stans valves instead of the Bontrager valves. I don't know if that's a contributor of if the Bontrager valves don't work at all.

    Then there have been posts about using Stans, Gorilla tape, etc.

    I've ordered a set of the AM 29er rims and was planning to use the Bontrager strips and valves (and sealant) for my setup. But wanted to see if anyone wanted to summarize the current thinking on going tubeless with the AM rims.
    I setup a pair of LB 650B 35mm wide rims tubless with 25mm Stan's tape and Stan's valve stems. It took 10 mins each and was one of the easiest rims I have ever setup tubeless.
    Safe riding,

    Vik
    www.vikapproved.com

  47. #5697
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    Quote Originally Posted by objectuser View Post
    Early on in the thread, it seems like there was a great deal of success in using the Bontrager rim strips for easy tubless conversion. However, that seems to have been primarily with what they now call their XC rim.

    Some later posts related to the wider AM rim indicate that using the Bontrager strips might not be so straight-forward. It seems some of these were using Stans valves instead of the Bontrager valves. I don't know if that's a contributor of if the Bontrager valves don't work at all.

    Then there have been posts about using Stans, Gorilla tape, etc.

    I've ordered a set of the AM 29er rims and was planning to use the Bontrager strips and valves (and sealant) for my setup. But wanted to see if anyone wanted to summarize the current thinking on going tubeless with the AM rims.
    The LB rim naming/labeling "system" (if you can call it that) is kind of confusing and haphazard. As such, if you are going to try to get some sort of clarity on the preferred methods for going tubeless, I would suggest you use the internal widths, and whether they are standard hooked, or the newer hookless design, to determine what people are running. i.e. 23mm-hooked vs. 22mm-hookless. Additionally, as if it wasn't confusing enough, there are people out there who have ordered extra beefy builds, with extra plies of carbon, but in the narrower more "XC" rim models/dimensions, and they have referred to them as "AM weight" or even just "AM", so it is tough to be sure what people are actually using unless you are really specific.

    Having said all of that, I can't claim to have a perfect recall of all 5700 posts in this thread, but my recollection of general trend is as follows.

    -When you say "AM 29er rims" I am guessing that you are referring to the 23mm-hooked model that seems to have the most users on here. My impression of the sentiment regarding tubeless setup was that Bontrager strips do provide a more secure seat for the bead of the tire due to their bump/barb/ridge that sits inboard of the tire bead, which helps to prevent burping. This can be observed by deflating a tire mounted on that setup, and trying to push it inward on the rim...it will offer a lot of resistance. Stans and Gorilla don't provide this additional security, but for many people with many tires, that additional security appears to be unnecessary. It also adds somewhere around 30g+ over Stans tape, with Gorilla in the middle, weight wise.

    -As you mention, there were people reporting problems with Bontrager strips sealing around the valve, but if memory serves, the recent mentions of that were on a hookless rims, which probably doesn't apply to you. That could have something to do with it, as the subtle differences in the hooked/hookless interior dimensions and shaping could make a substantial difference on this front. Or, as you point out, it could also be mixing valve/strip brands. Or user error. At this point, I don't think we really know.

    -There are people who have reported blowouts, but I am inclined to believe that is more a tire/rim tolerance issue, and not so much a bad strip/tape setup.

    I know it is probably not the absolute answer you want, but if you are at all of a weight weeny then I would start with the lightest setup (Stan's tape) and your preferred tire. Set it to your lowest ideal (reasonable) pressure and then take it on one of your bumpiest rides. See if you can get it to burp. If not, then additional bead security would seem to be unneeded for your tire/rim combo and riding style. Congratulations, you can run the lightest setup and save your self money too! If it does burp, then you can work your way up the bead security scale as slow/fast as you want, starting with thicker layers of tape, and ending with the Bontrager strips.

    For additional safety, I would suggest doing this on the rear only, as that wheel tends to see the greatest stresses (thus providing a good test bed) while also providing the lowest risk in case of a sudden loss of pressure...and it goes without saying bring a tube/pump.

  48. #5698
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    Thanks for your replies, guys.

    Yes, I am referring to the 23mm internal, clincher, 29er AM rim.

    I've not run tubeless before, so really I was looking for ease of conversion and reliability in the setup. If it's a pita, I'll likely go back to tubes.

    Kaiser, I really appreciate your suggestion of doing the rear tire first. That seems like sound advice. And thanks for your synthesis of the data on the Bontrager strips.

    Vik, glad yours went well. Stans seems to be the most widely used method. I may go that way at some point.

  49. #5699
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    Laced up my XC wheels late Fri night/Sat morning.

    LB Hookless carbon 27mm rims, UD Matte finish 32h
    Chris King SS/ISO hubs
    Dt Swiss Revolution spokes and alloy nipples (if they don't last I'll go to brass)
    Stans tape/Valve

    Weight savings vs the Arch EX and DT competition was over 300 grams. Stiffness vs alloy rims is off the charts




  50. #5700
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    (Cheap) Chinese Carbon Rims?

    What ERD did you use. I have a set on order but time is running short on getting them built in time and I would like to order some spokes.

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