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Discussion Starter · #1 ·
A guy that works for me bought a Fisher Paragon this year. He was having some problems with the tires rolling off the rim. The problem of 29er tires pealing off the rim is certainly not a new one...folding 29er tires seem to have a problem in this area. ANYWAY, we all hauled off to the Trek show in Madison last weekend and while there we brought this issue of the 29er tires up to the Bontrager tire guy. He said that Bonty is following the lead of WTB and seizing production of all folding bead 29er tires. And will only be offering steel bead tires for 29ers. Upon some follow-up I learned that WTB has already stopped production on all folding bead 29er tires. I checked with some on my suppliers and their inventory of folding bead 29er tires is either out or very low...indicating that they are not refilling their inventory. I am very much looking forward to Interbike to see if indeed the folding 29er tire is all but dead. I wonder what technological breakthrough must be reached to keep these tires on a rim?? Until, then I will continue to ride my folding Moto’s and hope for the best!! Guess I better buy up a bunch of what’s left before they are all gone.
 

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I recently bought some IRC Mythos kevlar beaded tires. I think the problem with the kevlar beads is when used with Stans. With a tube I don't think there's a problem.

It's unfortunate that this has occurred because 29ers really need light tires and kevlar beads is one way to get there.
 

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Discussion Starter · #3 ·
Guitar Ted said:
I remember reading a thread awhile back where somone stated that there are different qualities of Aramid fibers (the material used in most folding bead tires) available to use in tire manufacturing. I don't claim to be an expert, but this makes sense to me. It seems that WTB was having difficulty with one type of aramid fiber, and/ or it's construction in some of their earlier tires. I thought I understood that to be changed now, and that WTB was producing folders again.

I saw plenty of Aramid labled tires at the Trek Show. This would seem strange that now they would cease production of them without widespread dealer knowledge of it. Or was this "just" the 29"ers? A sad thing, if it's true!
Just 29ers have been stopped...26" production is rolling along just fine
 

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Discussion Starter · #4 ·
MikeDee said:
I recently bought some IRC Mythos kevlar beaded tires. I think the problem with the kevlar beads is when used with Stans. With a tube I don't think there's a problem.

It's unfortunate that this has occurred because 29ers really need light tires and kevlar beads is one way to get there.
Agreed. Well the guy at Bontrager who we talked to...who was the head of tire development, said it was one of his top priorities to solve this problem and to bring back the folding bead ASAP.
 

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Harmonius Wrench
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Bead qualities different?

I remember reading a thread awhile back where somone stated that there are different qualities of Aramid fibers (the material used in most folding bead tires) available to use in tire manufacturing. I don't claim to be an expert, but this makes sense to me. It seems that WTB was having difficulty with one type of aramid fiber, and/ or it's construction in some of their earlier tires. I thought I understood that to be changed now, and that WTB was producing folders again.

I saw plenty of Aramid labled tires at the Trek Show. This would seem strange that now they would cease production of them without widespread dealer knowledge of it. Or was this "just" the 29"ers? A sad thing, if it's true!
 

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What's up Dut?
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There has been plenty of talk about this subject and you can do a search until your hearts content....

...short story... true kevlar bead tires have not been known to fail when using stan's. Although, true kevlar bead tires are few in number (ie, IRC Notos and Mythos seem to be the only best option). Aramid bead tires (ie, Bontrager Jones and XR tires, Maxxis Ignitors, WTB folding tires, etc.) are a step down from true kevlar material. The aramid bead is slightly weaker. Although...keep in mind that there are no tires out there that are made to be run tubeless. Those of us that have tried it with success is the exception to the rule.

Back to the topic at hand... it will be sad to see the "end of folding 29er tires" but I doubt that will ever happen. We need to stop speculating and just wait for the cold hard facts.

But as long as speculation still gets thrown around.... I am very optimistic that Bontrager will step up and produce the first true UST tire and wheel for a 29er. Just don't know when that will happen.
 

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Discussion Starter · #7 · (Edited)
mdutcher said:
There has been plenty of talk about this subject and you can do a search until your hearts content....

...short story... true kevlar bead tires have not been known to fail when using stan's. Although, true kevlar bead tires are few in number (ie, IRC Notos and Mythos seem to be the only best option). Aramid bead tires (ie, Bontrager Jones and XR tires, Maxxis Ignitors, WTB folding tires, etc.) are a step down from true kevlar material. The aramid bead is slightly weaker. Although...keep in mind that there are no tires out there that are made to be run tubeless. Those of us that have tried it with success is the exception to the rule.

Back to the topic at hand... it will be sad to see the "end of folding 29er tires" but I doubt that will ever happen. We need to stop speculating and just wait for the cold hard facts.

But as long as speculation still gets thrown around.... I am very optimistic that Bontrager will step up and produce the first true UST tire and wheel for a 29er. Just don't know when that will happen.
I don't doubt what you are saying, I think this is a case on the old saying..."sometimes you have to a small step back in order to take a giant leap forward". The cold hard facts are that bonty stopped making folding 29er tires, and that WTB has haulted production of the current model 29er folding tires. Its back to the drawing board for a while... Thats why I say I can't wait till Interbike to what the whole story is.
 

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Harmonius Wrench
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Could you imagine the uproar?

Think about it. The 700c rim manufacturers all get together with the tire manufacturers to standardize rim and bead diameters. The Roadies would pee in their bibs! "You changed the wheel and tire standards for a tiny group of mountain biking freaks!" ;) :D
 

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Recovering couch patato
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Someone will HAVE to set up a big rim/tire manufacturers meeting, I've been calling for that for years. Either all 29" tires are over sized, or all rims undersize, maybe both. So far, only Stan's rims give a decent fit on 29" tires.
An inproper fit of bead and rim hook, either being larger than the other, can IMO only cause peak loads on parts of the bead. Bead is weaker than rim, bead breaks.
 

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well at least rim makers will have to explain tire makers how it's all supposed to work, because new tires fit loose on age-old rims.
 

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what he said!

Cloxxi's got it right IMO. I've cycled through tires for my 29ers and NONE HAVE HAD A GOOD FIT ON THE RIM!!! (Are you reading this manufacturers?) I have to say that I haven't tried Shwalbe or Maxxi's so can't speak for those.
 

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I have a full agenda for just 2 days of Eurobike (I leave this wednesday), but if I come across a tire brand I'll stop by and mention this. If someone writes a proper standard letter in Word, I'll print a bunch and deliver it personally, attn : Tire/Rim Quality Manager or whatever you think is most appropriate.
Even WTB tires on WTB rims and Bontrager tires on Bontrager rim fit loose, am I not right?

Who volunteers to write a letter on behalf of the MTBR 29" Board? Don't wiat, but start now! It's night here, I have to log off.
 

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HIKE!
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Rim bead size standards....

.... are and have been in place for a long time. The 622mm bead seat diameter for 700c road wheels has been the standard for a long long time. Hundreds of tires from 18c to 45c are easily had for road racing, cross, touring, commuting in both wire and folding beads. With pressures up into 120+ psi used for many models, it is doubtful the trouble is with the long existing and reliable 622mm bead seat diameter for rim manufacture.

Just as 26" atb rims are 559mm bead seat diameter, and have proven largely successful and safe in a variety of rim widths/cross sections, and now UST (with a special bead lock of sorts at the bead) and a variety of tires are and have been available in widths from 1" to 3" and pressures from 100+ psi on down. And there have been cases of a certain tire, or certain rim, or certain combo proving to be too loose, too tight it is a problem with something in the system falling out of spec.

Seems more likely the relatively new large diameter 700c (622 bead seat diameter) atb tires are missing the spec than the rims which have been under manufacture for many years and used successfuly with such a large range of tires and pressures. If a roadie can air up a folding bead 25mm tire to 120psi on a set of Mavic Speed City wheels, surely a folding tire can be made at 2 times (or so) the width and hold at 40 psi!

Google up the evolution of rim and tire standards on Sheldon Brown's nice website. It is pretty good info, the "700" designation once had an outer tread diameter of 700mm on any given tire, then the designation of A,B,C,or D told you how fat the tire was to achieve the given outer diameter, so 4 rim bead seat diameters existed to fill the "700" size wheel. 700 "C" is just the one size that has hung around for modern road bikes regardless of tire width, and is now used for the 29er wheel size.
 

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Very easy to do : measure the outside diameter of your rim. It should be 635mm, right, exactly 25 inches? If that's off, likely bead seat diameter is as well. I've seen many rims around the 633mm figure.
 

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HIKE!
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Bead Seat Diameter is what matters

The actual diameter of the Bead Seat is all that matters. A tall brake track (or short), can result in differing outer rim diameters. What the tire makers and rim makers build to is the 622mm Bead Seat Diameter, the diameter of the inner track that has the hook bead hanging over it. Make sense? the groove or hook into which the "Bead Seats", hence Bead Seat Diameter.

Measure a bunch of 26" atb rims, outer diameters can be all over the place 5 or more mm, but the bead seat diameter is 559mm, where the inner hook of the rim holds the bead. No significant troubles with the huge variety of tires for 26" 559mm bead seats.... so why can't the 29er/ 700c/ 622mm bead seat diameter atb tires get it right? The rims are all correct at 622 bsd....

630mm bead seat diameter is the 27" road tire standard...., and 635 is for the English 28" size.... see more here:

http://www.sheldonbrown.com/tire-sizing.html
 

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Stan's Rims

Cloxxki said:
Someone will HAVE to set up a big rim/tire manufacturers meeting, I've been calling for that for years. Either all 29" tires are over sized, or all rims undersize, maybe both. So far, only Stan's rims give a decent fit on 29" tires.
An inproper fit of bead and rim hook, either being larger than the other, can IMO only cause peak loads on parts of the bead. Bead is weaker than rim, bead breaks.
I have had the Bonti's, Exi's and Ignitors both with tubes and tubeless with Stans rims. They fit tight. I only have tested the Ignitor tubeless and it works great. The Bonti rims and tires are really loose.
 

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The reason why a manufacturer would cease the production of their tires is because of people not using their product the way it was intended. I am a big offender of that. I do agree that sometimes taking a step backward is always a good thing when you are trying to make a leap forward. However, has that occurred yet with WTB? I don't buy WTB tires so I am not sure if they are back to producing folding bead tires yet or not. I would hope that they would tighten the tolerances or do whatever to make them work as people would want to use them, however they want to use them. How many people out there take and huck their XC bike off of some big rock or even take it down some truly technical downhill? I am a big offender of that as well. We are using our bikes, at times, the way that the manufacturer has not intended them to be used. Have they ceased production on XC frames? Not likely. Bottom line is this... we want a tubeless (true UST) tire and wheel combo. We want something that is relatively lightweight. And most of us out there will do the ghetto setup to accomplish that. The manufacturers know this, if they don't, then they are being ignorant.

I have been running tubeless on my 29er for a couple of years now. I have not had any issues with my setups. I have spoken with people that actually race on these setups and it seems to be a proven thing for them (ie, Cameron Chambers). Bontrager rims seem to be about the best rims out there for tubeless setups. Match that up with IRC Mythos or Notos and you should have a great match. I have also had great success with American Classic disc rims as well.

At my last race, Mavic was present there. They have had so many people asking them when they were going to make a tubeless Crossmax 29er wheelset. They told me that they hear our stories and that it is not going on deaf ears. It is that the people at Mavic headquarters thinks that the 29er thing is a fad or a niche. That is quite sad when you think about how much the 29er has evolved over the last several years. I am with Cloxxki, we need to yell a lot louder. 29ers are here to stay. If I could make my voice heard, I would. If I get the chance to make my voice heard, I do. If I had the engineering degree and a butt load of money, I would make the stuff myself.
 
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