Was having a talk with my brother about Carbon Clinchers the other day and he told me about a video he watched where a guy on youtube said the braking surface on the clincher can overheat when descending and cause the rim to fail. I didn’t believe him and searched myself and sure enough there it is.
There is a guy in Australia named Raul that is in a few different videos about carbon and he seems to know his stuff. Speaks with an air of authority on the subject and backs it up with some pretty in-depth knowledge on all things carbon fiber.
In the video, basically an interview from a rider in Aus that posts videos ( Cycling Maven) Raul claims carbon clinchers absolutely can fail while descending and the industry knows it s a pretty big problem and are trying to figure it out; one way being the move the disc brakes.
Take a look and see if it gives you pause about carbon clinchers. My brother has a set of 60s that he says he won’t ride anymore. Maybe an overreaction but I’m not so sure.
Was having a talk with my brother about Carbon Clinchers the other day and he told me about a video he watched where a guy on youtube said the braking surface on the clincher can overheat when descending and cause the rim to fail. I didn’t believe him and searched myself and sure enough there it is.
There is a guy in Australia named Raul that is in a few different videos about carbon and he seems to know his stuff. Speaks with an air of authority on the subject and backs it up with some pretty in-depth knowledge on all things carbon fiber.
In the video, basically an interview from a rider in Aus that posts videos ( Cycling Maven) Raul claims carbon clinchers absolutely can fail while descending and the industry knows it s a pretty big problem and are trying to figure it out; one way being the move the disc brakes.
Take a look and see if it gives you pause about carbon clinchers. My brother has a set of 60s that he says he won’t ride anymore. Maybe an overreaction but I’m not so sure.
Any experience from the folks in here?
I think this has been common knowledge for a long time. it is why for the first 6 years of CC tech I only road Zipps as I trusted their brake track testing. They are moving to discs because it forces another upgrade cycle and manufacturers like upgrade cycles. Now whether they always knew CC would be a stop-gap to drives sales, well that is what I would love to know.
When carbon clinchers first came out, there was overheating problems. Now, probably not due to increased temp ranges on the resins. Don’t drag your brakes down a mountain and you will be fine. In the future, we will all be on disc brakes anyway.
I agree with both of you. But, I still tend to think this can’t happen that often with the current Carbon Clinchers and even if you tend to ride the brakes going downhill. I haven’t heard or read about a total failure on a carbon clincher because of the rim failing due to heat. Just because I haven’t read it doesn’t mean it doesn’t happen, but felt I would hear more about it if it was a major issue.
I don’t plan to go to Disc anytime soon as no reason. I like the stuff I have and if anything, will just go to aluminum brake track with fairing for deeper wheel, HED or Flo etc…
I haven’t heard or read about a total failure on a carbon clincher because of the rim failing due to heat. Just because I haven’t read it doesn’t mean it doesn’t happen, but felt I would hear more about it if it was a major issue.
A quick Google search would have shown you plenty of examples. Here’s one:
Carbon does not transfer heat as well as aluminum, so there is more temperature rise on carbon rims (tubular or clincher) during braking. The issue is if the resin in the composite can handle the temperature (the carbon fibers themselves are fine, but only perform their job when held in place by the resin). All high quality wheel makers (Zipp, Enve, Reynolds, Mavic, etc.) use high temperature resins that can withstand the extra heat (so do most of the open mold Chinese wheels these days, but no guarantees).
In the earlier days of carbon wheels there were some issues with rims warping from the heat during extreme descents, but that was years ago before mfgs upgraded their resins.
Edit: That picture of a warped CC is eight years old.
I haven’t heard or read about a total failure on a carbon clincher because of the rim failing due to heat. Just because I haven’t read it doesn’t mean it doesn’t happen, but felt I would hear more about it if it was a major issue.
A quick Google search would have shown you plenty of examples. Here’s one:
I haven’t heard or read about a total failure on a carbon clincher because of the rim failing due to heat. Just because I haven’t read it doesn’t mean it doesn’t happen, but felt I would hear more about it if it was a major issue.
A quick Google search would have shown you plenty of examples. Here’s one:
Carbon does not transfer heat as well as aluminum, so there is more temperature rise on carbon rims (tubular or clincher) during braking. **The issue is if the resin in the composite can handle the temperature (the carbon fibers themselves are fine, but only perform their job when held in place by the resin). All high quality wheel makers (Zipp, Enve, Reynolds, Mavic, etc.) use high temperature resins that can withstand the extra heat (so do most of the open mold Chinese wheels these days, but no guarantees). **
In the earlier days of carbon wheels there were some issues with rims warping from the heat during extreme descents, but that was years ago before mfgs upgraded their resins.
Edit: That picture of a warped CC is eight years old.
AND, a big part of the whole issue is that it’s pretty hard to find a high Tg resin that’s also not so brittle that it ends up causing rim cracking in general use…a regular “damned if you do, damned if you don’t” type of design tradeoff. Those resins exist, but they aren’t cheap.
So, are carbon clinchers safe? Definitely not inexpensive ones…and even some “expensive” ones as well.
In any case, WHY do people think rims need to be made of ONLY carbon fiber composite? Is it mass? If so, then why are they so eager to add the mass of hub-discs to allow full carbon rims, when they could add LESS mass by just selecting/designing rims with aluminum brake tracks and carbon “caps”? They’re also less expensive…and no less aero than their all-carbon counterparts. One of life’s great mysteries, I guess… :-/
Was having a talk with my brother about Carbon Clinchers the other day and he told me about a video he watched where a guy on youtube said the braking surface on the clincher can overheat when descending and cause the rim to fail. I didn’t believe him and searched myself and sure enough there it is.
There is a guy in Australia named Raul that is in a few different videos about carbon and he seems to know his stuff. Speaks with an air of authority on the subject and backs it up with some pretty in-depth knowledge on all things carbon fiber.
In the video, basically an interview from a rider in Aus that posts videos ( Cycling Maven) Raul claims carbon clinchers absolutely can fail while descending and the industry knows it s a pretty big problem and are trying to figure it out; one way being the move the disc brakes.
Take a look and see if it gives you pause about carbon clinchers. My brother has a set of 60s that he says he won’t ride anymore. Maybe an overreaction but I’m not so sure.
Any experience from the folks in here?
No firsthand experience (Floridian here, lol) but brake track failure is 100% a problem with carbon clinchers going down steep, prolonged descents. Personally, I’ll only ride Zipp carbon clinchers because of this issue. Another issue you could potentially face is your tube failing due to heat buildup if you’re using latex with carbon clinchers.
Two of those are Chinese open mold wheels, and the ENVE was damaged when the clincher came off and the rim was running on asphalt (could have been due to a flat, hard to tell).
Personally I’d steer clear of open mold wheels if I did a lot of long descents, but would feel totally comfortable with Zipps, ENVEs, etc. I know a lot of folks that use them on the climbs here with no issues.
Personally I use HEDs (aluminum rim, carbon fairing), because to Tom A’s point I can get great breaking and good aerodynamics for a lot less $$$. I wouldn’t turn down a pair of 808s though :).
I’ve done lots of hilly races where everyone was using brakes hard enough to smell burning carbon, and my Zipp firecrest 404’s have held up fine. Maybe they will fail on my someday, but so far they have been great. So I think it really depends on the manufacturer, rider weight, and maybe luck?
