Blow-out - Michelin latex tube on SL23 rim

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sawyer
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by sawyer

@bratz - fair enough. What was the issue with veloflex tubs?

I suspect you're right that most of the issues people have are installation/contamination issues, though inherently a latex inner is more likely to "find" any weakness in the rim/tyre envelope due to its elasticity ... and of course extreme conditions are more likely to create weaknesses

To add to this, for the same reason I suspect latex tubes deflate even faster than butyl in a blow-out situation. Not much in it of course, but even a split second can help when you have to control stop the bike at speed
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bratz
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by bratz

@sawyer - no issues with veloflex tubs "yet" as I havent convert to it. As veloflex tires are not known for their durability, im testing the "cheaper" version to determine whether these awesome tires will withstand my local roads. So far im pretty impressed by their clinchers even though they wear much faster compared to michelin and conti tires. I prefer to race/train on same wheels combo or maybe i'll keep the clinchers for training and use tubs for racing once i get onto tubular bandwagon.

mattr
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by mattr

FWIW, i found that the added pliability of latex, and it's inherent stickiness, means that under heavy braking the tube allows the tyre/tube combination to walk round the rim. Eventually leading to 1/4 of the tube being stretched round 3/4 of the tyre. Then it fails. Pops hugely and twangs back into place. So you've no evidence.

Only way i found out was removing a tyre and tube where the tube was so stuck to the tyre i needed to peel it off. And it was seriously stretched. Almost to the 1/4-3/4 level.

I carried on using them after this, but used masses of talc (really masses) and left the tyre partially deflated when not in use. (was in raceday only wheels, so not a big deal).

Raineman
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by Raineman

From personal experience and what I've read, latex tubes are faster and nicer to ride but require much greater care in their installation and use. This is why some wheel companies, particuarly with carbon clinchers, don't recomend them as they are unable to guarantee that the user is completely competant. Thus it is easier to tell no one to use latex tubes than have a large number of riders complain publicly about blowouts.

sawyer
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by sawyer

bratz wrote:@sawyer - no issues with veloflex tubs "yet" as I havent convert to it. As veloflex tires are not known for their durability, im testing the "cheaper" version to determine whether these awesome tires will withstand my local roads. So far im pretty impressed by their clinchers even though they wear much faster compared to michelin and conti tires. I prefer to race/train on same wheels combo or maybe i'll keep the clinchers for training and use tubs for racing once i get onto tubular bandwagon.


I have been impressed by Vittoria SRs ... 24mm vs 23mm is noticeable and they are very grippy if not the very fastest.

Other than that the new CXs and the SCs (same tyre other than sidewall) are fast if a bit more delicate
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WMW
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by WMW

sawyer wrote:Implicit in your post however, and supported by real world experience, is that it requires
a lot of care and is easy to get wrong.


I talc the tube and inside of the tire and make sure the tube is "happy" (not kinked, twisted, folded, etc) before putting the 2nd bead on.

I've never pinched a tube when installing it. Not once. I don't understand what people who pinch them are doing. Do you install it without any air? No talc?
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WMW
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by WMW

mattr wrote:FWIW, i found that the added pliability of latex, and it's inherent stickiness, means that under heavy braking the tube allows the tyre/tube combination to walk round the rim. Eventually leading to 1/4 of the tube being stretched round 3/4 of the tyre. Then it fails. Pops hugely and twangs back into place. So you've no evidence.


WTF?! I've never heard of that. Definitely never happened to me.

Latex isn't sticky after you coat the tire and tube with talc.
formerly rruff...

sawyer
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by sawyer

WMW wrote:
sawyer wrote:Implicit in your post however, and supported by real world experience, is that it requires
a lot of care and is easy to get wrong.


I talc the tube and inside of the tire and make sure the tube is "happy" (not kinked, twisted, folded, etc) before putting the 2nd bead on.

I've never pinched a tube when installing it. Not once. I don't understand what people who pinch them are doing. Do you install it without any air? No talc?


HI - I don't ride latex inner tubes so couldn't tell you

What is beyond doubt is that a lot of people struggle with these - and are living dangerously. Gotta be 100% sure your front inner is safe before hitting 80kmh downhill ...
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rmerka
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by rmerka

Check the tire for a small cut where the tube popped. A small cut that would be ok for butyl can allow the latex to squeeze out and pop. Could be caused even by rough chipseal. Has happened to me twice.

bm0p700f
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by bm0p700f

I have been running latex tube in my carbon clincher for a long while and never had a blow out. Had un explained punctures before at the valve but the hole is always small never a big tear. Had blowout on butyl tubes though when the tyre gets cuts nevr had a latex tube blow out. They always leak more slowly. In book they are safer. Also latex sealant in them actually works at sealing small puncture so preloading can work.

mattr
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by mattr

WMW wrote:WTF?! I've never heard of that. Definitely never happened to me.
That's nice. It has to me.
WMW wrote:Latex isn't sticky after you coat the tire and tube with talc.
You'll be amazed to hear that many people will just look at you blankly when you ask why they haven't talced the tube/tyre they are about to fit. Including (unfortunately) a couple of mechanics I've had the misfortune to deal with.

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spookyload
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by spookyload

mattr wrote:FWIW, i found that the added pliability of latex, and it's inherent stickiness, means that under heavy braking the tube allows the tyre/tube combination to walk round the rim. Eventually leading to 1/4 of the tube being stretched round 3/4 of the tyre. Then it fails. Pops hugely and twangs back into place. So you've no evidence.

Only way i found out was removing a tyre and tube where the tube was so stuck to the tyre i needed to peel it off. And it was seriously stretched. Almost to the 1/4-3/4 level.

I carried on using them after this, but used masses of talc (really masses) and left the tyre partially deflated when not in use. (was in raceday only wheels, so not a big deal).

You are saying the tire will shift on the rim under heavy braking? I call Shenanigans on that. The contact area of a tire on the rim has far too much friction for an inflated tire to do that. The only time that could possibly happen would be with a flat tire. Sure I have seen drag cars do that when they burn out, but you are honestly saying a bike tire will do that while inflated? BS.

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pdlpsher1
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by pdlpsher1

Even with extreme care in mounting a latex tube I have had several that spontaneously ruptured with no apparent cause. This has never happened on a butyl tube. IMHO the benefit doesn't justify the risk of severe injury caused by a blow out.

Svetty
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by Svetty

I'm 99.9% sure that there was no installation issue. I am very careful when fitting the tube/tyre and had ridden several hundred miles on this wheel without problems including 70+ kmh decent. On this occasion I was decending a 17% hill with a strong tailwind. The lack of air braking necessitated fairly heavy use of the brakes= heating of the rim= failure of latex tube. The tire is unblemished.
In retrospect the pressure was slightly higher than optimal and probably contributed to a 'perfect storm' scenario. ..........

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WMW
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by WMW

Svetty wrote:The lack of air braking necessitated fairly heavy use of the brakes= heating of the rim= failure of latex tube. The tire is unblemished.


Tubes have no stress on them when properly installed. The tube won't fail because it gets hot, because it isn't doing anything but sitting there pressed up against the container. So there must be some other explanation.

What did the hole look like? How big?
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