Blowouts

Chips Lovell

Aside from the fact that carbon clinchers are a bad idea in general in my opinionl, you should never use latex tubes with carbon clinchers. Most manufacturers will advise against it.

cdaly_

harringtonp wrote: »

I checked my other wheels and noticed vertical marks on the sides of the tyres on two of them, see images. The tyres are Michelin Pro3.

Whatever about the tyres, those mavic rims are looking worn...

De Bhál

Jep Gambardella wrote: »

Aside from the fact that carbon clinchers are a bad idea in general in my opinionl, you should never use latex tubes with carbon clinchers. Most manufacturers will advise against it.

just wondering why you think carbon clinchers are a bad idea? I don't know much about them.

07Lapierre

De Bhál wrote: »

just wondering why you think carbon clinhers are a bad idea? I don't know much about them.

They get very hot under heavy braking. (Hotter than Alloy rims anyway). Latex tubes are very thin, so more prone to blowouts when they heat up.

De Bhál

07Lapierre wrote: »

They get very hot under heavy braking. (Hotter than Alloy rims anyway). Latex tubes are very thin, so more prone to blowouts when they heat up.

would this be something you'd worry about in the hills of this country or longer alpine type descents

07Lapierre

De Bhál wrote: »

would this be something you'd worry about in the hills of this country or longer alpine type descents

Depends on how good you are at descending! (Stay off the brakes)

iwillhtfu

De Bhál wrote: »

would this be something you'd worry about in the hills of this country or longer alpine type descents

I have carbon rims and for the most part they're fine on our descents but it's not really the gradient it's how much braking you use. If you're trailing the brakes while descending this will create heat.

Generally if I plan to go on a hilly route with a lot of climbing and descending I'll use different wheels. The carbon rims I have are deep section I use them mainly in Triathlon races but occasionally on a road spin. I've never had an issue with them over heating but I have experienced brake fade on a few spins.

Chips Lovell

De Bh103975684 wrote:

just wondering why you think carbon clinchers are a bad idea? I don't know much about them.

I don't think carbon is a suitable material for a clincher rim. As Lapierre says, they retain heat more than allot runs, increasing your chance of a blowout. And if you flat, there's a risk that the rim will get damaged through contact with the road surface, as happened to the OP.

iwillhtfu

Jep Gambardella wrote: »

I don't think carbon is a suitable material for a clincher rim. As Lapierre says, they retain heat more than allot runs, increasing your chance of a blowout. And if you flat, there's a risk that the rim will get damaged through contact with the road surface, as happened to the OP.

They're perfectly suitable as a clincher wheel or at least as much as a tub and I'd prefer a full carbon wheel than these laminated carbon fairing you see.

Anything carbon is easily damaged when dragged along the ground including your frame. If op had not of breaked to the point of skidding on the rim the damage may not have been as bad but I understand with a blowout the sudden reaction to jumping on the breaks.

jntsnk

If you do have a blowout does that just mean a puncture or the carbon rim be damaged as well

iwillhtfu

jntsnk wrote: »

If you do have a blowout does that just mean a puncture or the carbon rim be damaged as well

It depends how bad it is but generally the damage is done when the rim comes into contact with the road but yes it can blow out the sidewall of the rim.

Chips Lovell

iwillhtfu wrote: »

They're perfectly suitable as a clincher wheel or at least as much as a tub and I'd prefer a full carbon wheel than these laminated carbon fairing you see.

Anything carbon is easily damaged when dragged along the ground including your frame. If op had not of breaked to the point of skidding on the rim the damage may not have been as bad but I understand with a blowout the sudden reaction to jumping on the breaks.

I'd have to disagree with this. Clincher and tubulars rims are very different. With a clincher, the braking surface is directly next to the the tyre and tube. With tubulars, the tyre sits above it, away from the heat.

And yes, a carbon frame will be damaged if ground into the road but your wheels are the part of the bike that are in permanent contact with the road.

iwillhtfu

Jep Gambardella wrote: »

I'd have to disagree with this. Clincher and tubulars rims are very different. With a clincher, the braking surface is directly next to the the tyre and tube. With tubulars, the tyre sits above it, away from the heat.

And yes, a carbon frame will be damaged if ground into the road but your wheels are the part of the bike that are in permanent contact with the road.

Disagree all you like it makes it no more right to be honest.

You mean your tyres are permanently in contact with the road. By your logic the frame is equally in contact with the road as the rims.

It's also more likely you'll roll a tyre on a tubular due to heat build up let's not forget it's only glue securing your tyre to the rim. As for the breaking surface being away from the tyre on a clincher you are aware heat dissipates throughout the rim.

Anyway I digress. I disagree with your initial statement and having ridden both tubs and clinchers I would pick clincher over tub every time unless of course you've a team car following you everywhere.

Lumen

I came across this thread late after it was referred to from another.

I've read the contention that carbon clinchers are OK on descents if you know how to brake properly. I've probably even written that myself.

But I terminally warped my front carbon clincher last year descending Red Lane. It's a very technical, twisty and bumpy descent and it was wet which limited my opportunities for hard braking. It's possible that someone braver or more skilful could have managed it, but I couldn't despite being aware of the limitations of my rims.

So the idea that this problem requires "alpine" descents is not true, in my experience.

Of course it's likely that there was something wrong with the rim already. I was getting pulsing under braking since they were new, but this generation of wheels (2010 maybe) tended to do that. I did get lots of warning as the pulsing got worse over the descent, but I carried on going as I was curious to explore the failure mode.

After checking the rim at the bottom I cycled home very carefully. There was one more hill which I descended slowly using the rear brake only.

cdaly_

Lumen wrote: »

I came across this thread late after it was referred to from another.

I've read the contention that carbon clinchers are OK on descents if you know how to brake properly. I've probably even written that myself.

But I terminally warped my front carbon clincher last year descending Red Lane. It's a very technical, twisty and bumpy descent and it was wet which limited my opportunities for hard braking. It's possible that someone braver or more skilful could have managed it, but I couldn't despite being aware of the limitations of my rims.

So the idea that this problem requires "alpine" descents is not true, in my experience.

Of course it's likely that there was something wrong with the rim already. I was getting pulsing under braking since they were new, but this generation of wheels (2010 maybe) tended to do that. I did get lots of warning as the pulsing got worse over the descent, but I carried on going as I was curious to explore the failure mode.

After checking the rim at the bottom I cycled home very carefully. There was one more hill which I descended slowly using the rear brake only.

:eek:

doozerie

Lumen wrote: »

I came across this thread late after it was referred to from another.

I've read the contention that carbon clinchers are OK on descents if you know how to brake properly. I've probably even written that myself.

But I terminally warped my front carbon clincher last year descending Red Lane. It's a very technical, twisty and bumpy descent and it was wet which limited my opportunities for hard braking. It's possible that someone braver or more skilful could have managed it, but I couldn't despite being aware of the limitations of my rims.

There was a downhill racing event held on that hill a few years back. I had a brief conversation with one of the riders competing in it early on who, from what I recall, said he was a French former pro road racer.

My abiding memory of that day is seeing his bike summersaulting gracefully through the air (well, okay, it was graceful while in the air, less so each time it hopped off the ground) for the last stretch. I think it even reached the finish line. He didn't, he was in heap in the ditch, though I saw him again later and he seemed relatively okay (wearing a sling, but conscious and chirpy).

That descent takes no prisoners.

Alek

_Each time_ I find myself going down Red Lane I make promise to only ever climb it from now on...

Lumen

Racing on closed roads is easier on rims because you don't have to bee able to "stop in the space you can see to be clear and is likely to remain so", the only limit is cornering grip.

Obvs going faster brings other terrors.

On open roads you need to be going slow enough to stop.

Red Lane is particularly problematic due to blind bends and narrowness, plus the usual gravel and broken, bumpy surface. You may come round a corner to find the road fully blocked by cars negotiating a pass or a car ascending at speed in the middle of the road, in which case the hedge would look relatively appealing as a destination.

loyatemu

Alek wrote: »

_Each time_ I find myself going down Red Lane I make promise to only ever climb it from now on...

neither option is appealing TBH

Alek

neither option is appealing TBH

At least one has a proper HTFU quality, the other is downright butt clenching :pac: