Road Bike, Cycling Forums banner
1 - 20 of 23 Posts

·
Registered
Joined
·
456 Posts
Discussion Starter · #1 ·
I'm considering purchasing a carbon clincher wheelset and looking for feedback from you industry dudes in respect to what you see as the most reliable, least amount of warranty claims/failures. My research points me towards Enve 3.4's specifically w/ DT 240's? Non-Asian made is important to me, but not a deal breaker.
 

·
Höchstgeschwindigkeit
Joined
·
1,378 Posts
Have had a great run with Enve Classic 65s and CK hubs for 30k+ hard ridden trouble free miles. The only hub perhaps better due to easier maintenance imho is WI. DTs to me fall in behind WI and CK.
 

·
Registered
Joined
·
5,347 Posts
If your criteria is trouble free you should skip carbon rims. At the very least you're going to have to swap brake pads when changing wheels and braking will not be as good, especially in the wet. There's also the possibility of overheating the rims on descents.
 

·
Banned
Joined
·
3,297 Posts
If your criteria is trouble free you should skip carbon rims. At the very least you're going to have to swap brake pads when changing wheels and braking will not be as good, especially in the wet. There's also the possibility of overheating the rims on descents.
Perhaps this is the true basis of the worldwide conspiracy to make everyone adopt disc brakes.
 

·
Registered
Joined
·
192 Posts
Trouble free, people here get hung up on that phrase. I guess my 40+ spoke cruiser wheels are trouble free...

So, carbon are fun to ride and they look great. I think your question is more on the cost/durability question. Do you want them to last a long time, or just be sure you don't get stranded somewhere?

You are probably right about clincher, easier to maintain than tubulars for most. Much easier to change a flat.

What can go wrong with the wheel? The hub, the spokes and the rim, right? Most of the lower cost wheels seem to use machined AL hubs. They all take some maintenance, but not bad. The spokes; low count puts more stress on them. The rim - braking has been the long time culprit here. Proper brakes and braking style will help. Carbon won't brake as well as alloy.

There also seem to be two carbon options; high priced and lower priced. high being the Zipp and Enve types. I went with Boyd 44mm clinchers and they fall into the lower priced option. Links in here are to similar price ranged wheels.

I like the Boyds as I was able to get a higher spoke count. Less stress on the spokes. The hubs have easily serviceable parts should something go wrong there. Like most, the rims are using newer epoxy and are standing up to harder braking. I think most are good there these days.

The biggest thing for durability - how you ride. Avoid the big holes, don't rub on curbs and other things that actually hit the rim. Don't ride them on a flat. Learning how to bunny hop the bad bumps or soak up the impact going over a curb will help too.

But I ramble. It is probably right that you shouldn't buy carbon for long term durability. They are fun to ride, look cool and for me, they motivate me to get out more often. I'm happy with the couple thousand miles I have on my carbons across our locally crappy roads.
 

·
Registered
Joined
·
7,197 Posts

·
Registered
Joined
·
6,841 Posts
I'm also very intrigued about the new Cosmic Carbon Pro SL clinchers!

One big feature is the claimed 200C degree brake track temp. This is 392F, which is a significant improvement over the current Tg of ~350F of today's highend carbon rims.

However, I would like to ask Mavic these questions:

1) why not make it 50mm deep?? I'll take aero gain over minuscule 30g weight gain any day!

2) what about anti-bite feature for the aluminum freebody? Or is the freebody made of ti?



Also, quoting Cyclingtips article above:

The Cosmics and Ksyriums are set to retail in the US for US$2,200 for both rim- and disc-brake versions. UK buyers can expect to pay £1,450 for rim-brake Cosmics while the disc-brake version will cost £50 more. The Ksyriums will retail for £1,500 and £1,575, for the standard and disc versions, respectively.
hmm I don't get the pricing.

1) shouldn't the rim version cost MORE than then disc version since more work has to be done on the rim version, e.g., treatment of the brake tracks for high heat resistance. This is great if you're a rim buyer, but I'd be asking why if I were a disc buyer.

2) Why is the disc version be higher than the rim version for UK folks?

3) Also for the UK, why is the Ksyrium cost more than the Cosmic? I'd think the Cosmic would cost more due to more material, but maybe the Kysrium costs more due to lower yield in the UK??

Anyway, the pricing seems to be most beneficial for US buyers of the Cosmic rim version, no? To conclude, I see weird pricing discrepancy regarding:
1) rim vs disk
2) Cosmic vs Ksyrium
3) for UK market
 

·
Registered
Joined
·
7,197 Posts
I'm also very intrigued about the new Cosmic Carbon Pro SL clinchers!

One big feature is the claimed 200C degree brake track temp. This is 392F, which is a significant improvement over the current Tg of ~350F of today's highend carbon rims.

However, I would like to ask Mavic these questions:

1) why not make it 50mm deep?? I'll take aero gain over minuscule 30g weight gain any day!

2) what about anti-bite feature for the aluminum freebody? Or is the freebody made of ti?



Also, quoting Cyclingtips article above:



hmm I don't get the pricing.

1) shouldn't the rim version cost MORE than then disc version since more work has to be done on the rim version, e.g., treatment of the brake tracks for high heat resistance. This is great if you're a rim buyer, but I'd be asking why if I were a disc buyer.

2) Why is the disc version be higher than the rim version for UK folks?

3) Also for the UK, why is the Ksyrium cost more than the Cosmic? I'd think the Cosmic would cost more due to more material, but maybe the Kysrium costs more due to lower yield in the UK??

Anyway, the pricing seems to be most beneficial for US buyers of the Cosmic rim version, no? To conclude, I see weird pricing discrepancy regarding:
1) rim vs disk
2) Cosmic vs Ksyrium
3) for UK market
I can't even begin to explain away all of these, but I do know that some manufacturers consider a 40mm rim depth to be the sweet spot for the combination of aerodynamics, weight, and avoiding crosswinds. You get more than enough aero benefit, the wheels can still be super light, and they are easier to handle on windy days (that's the idea anyways).
 

·
Registered
Joined
·
5,613 Posts
If your criteria is trouble free you should skip carbon rims. At the very least you're going to have to swap brake pads when changing wheels and braking will not be as good, especially in the wet. There's also the possibility of overheating the rims on descents.
This is outdated. I used to think disc brakes were going to be the only viable solution, but new brake track/pad technology is much better now. I crashed on an older generation Reynolds wheel due to a rim failure (a 50k hospital bill...), so my recommendation of newer generation carbon rims comes from that background.

My personal choice is Reynolds. The assault, attack. strike combinations are a good solution for everyday riding and racing. Better pricepoint than enve/zipp. Also, they are now tubeless so concerns about heating a tube (which is what led to failures before) can be completely avoided if you want. I have ridden attacks in mountains for 2 years daily - I weigh 170-175 lbs and am a fast descender. I haven't had to true them once. The new power brake pads and ctg brake track result in better braking performance than my alloy wheels (e.g, Jet 6). They are 25 mm wide, so you can also use reduced psi. I've also used Reynolds in powertap amp wheelsets (made for them by Reynolds).
 

·
Registered
Joined
·
6,841 Posts
This is outdated. I used to think disc brakes were going to be the only viable solution, but new brake track/pad technology is much better now. I crashed on an older generation Reynolds wheel due to a rim failure (a 50k hospital bill...), so my recommendation of newer generation carbon rims comes from that background.

My personal choice is Reynolds. The assault, attack. strike combinations are a good solution for everyday riding and racing. Better pricepoint than enve/zipp. Also, they are now tubeless so concerns about heating a tube (which is what led to failures before) can be completely avoided if you want. I have ridden attacks in mountains for 2 years daily - I weigh 170-175 lbs and am a fast descender. I haven't had to true them once. The new power brake pads and ctg brake track result in better braking performance than my alloy wheels (e.g, Jet 6). They are 25 mm wide, so you can also use reduced psi. I've also used Reynolds in powertap amp wheelsets (made for them by Reynolds).
Even though there was concern about heating the inner tube, and some folklore would say that it was the tube that somehow melted and exploded, but my understanding is that this was not the mode of carbon rim failure. My understading is that it was the brake tracks that started to melt and deteriorate, causing the tracks (which is a support structure) to collapse and thus not be able to hold back the now higher pressured tire/inner tube. And when the brake tracks collapse, so goes the tire and inner tube. The collapse of the brake tracks would also affect tubeless tires too. But with tubeless tires, you could usually run 10 psi lower, and by running 10 psi lower to start, it allows you a little tiny bit of margin of safety in the event of brake tracks over heating.

But like you said, this issue was mainly with the older carbon rims. New rims are good for 10%-12% gradient easily. But if it gets to 15%, then you still gotta be smart about your braking method, i.e., modulate. If it gets to 20%, then bring in the disc definitely. Fortunately there aren't that many 20% gradient descent out there, because let's be honest here at 20% even automobiles will burn up their disc brakes easily too. I occasionally see cars with burnt (smoking) brakes going down Mt Baldy, and plenty of cars will give off the brake odor too (but not yet burnt completely). Mt Baldy is a 4 miles at almost 10% descent, but the first 2 mile of descent is the most difficult because it has some 15-18% gradient leading into a hairpin which pretty much requires full grab of the brakes, no modulating much here.

Also, I see so many guys not letting out a puff or two of air before a big descent. This would let out 10-20 psi which is fine as these psi will be refilled on the descent anyway. Yet 10 out 10 guys won't do this. And when I do it, they look at me like "what are you doing letting air out of your tire".
 

·
Registered
Joined
·
580 Posts
I have had zero issues with my Williams System 38's for over 2 years. Williams had rim redesign since I bought mine and I believe the brake track was redone. I have no stopping issues though riding in the rain is something I don't do with them.
 

·
Registered
Joined
·
5,347 Posts
Newer rims withstand brake heat better. But they're not to the level of aluminium yet. Whether that's a problem depends on the descents you do (steep and technical being the worst) and your confidence on descents.
 

·
Registered
Joined
·
6,841 Posts
Anyone familiar with the Levi's grand fondo? There's one particular sharp hairpin that's super steep (over 20% I believe), and it's infamous for killing carbon rims under hard braking. I think Zipp said that when they developed their Firecrest series, they had this hairpin in mind. But this was back in 2010 or so. Since then, carbon rims braking have improved across all manufacturers. (Mavic's claim of 200C is impressive, and also goes to show that carbon rim braking is still improving. Maybe future carbon rim makers will follow Mavic). So unless you plan to attack 20% gradient hairpins, I wouldn't worry much. And to be honest, a 20% gradient into a hairpin is just crazy to attempt even on disc brake, because the limiting factor will be as much about tire traction too. I'd avoid descending anything over 20% due to health and longevity factor, or go with aluminum rims. No issues whatsoever with aluminum on 20% for me.
 

·
Registered
Joined
·
5,613 Posts
Even though there was concern about heating the inner tube, and some folklore would say that it was the tube that somehow melted and exploded, but my understanding is that this was not the mode of carbon rim failure. My understading is that it was the brake tracks that started to melt and deteriorate, causing the tracks (which is a support structure) to collapse and thus not be able to hold back the now higher pressured tire/inner tube. And when the brake tracks collapse, so goes the tire and inner tube. The collapse of the brake tracks would also affect tubeless tires too. But with tubeless tires, you could usually run 10 psi lower, and by running 10 psi lower to start, it allows you a little tiny bit of margin of safety in the event of brake tracks over heating.

But like you said, this issue was mainly with the older carbon rims. New rims are good for 10%-12% gradient easily. But if it gets to 15%, then you still gotta be smart about your braking method, i.e., modulate. If it gets to 20%, then bring in the disc definitely. Fortunately there aren't that many 20% gradient descent out there, because let's be honest here at 20% even automobiles will burn up their disc brakes easily too. I occasionally see cars with burnt (smoking) brakes going down Mt Baldy, and plenty of cars will give off the brake odor too (but not yet burnt completely). Mt Baldy is a 4 miles at almost 10% descent, but the first 2 mile of descent is the most difficult because it has some 15-18% gradient leading into a hairpin which pretty much requires full grab of the brakes, no modulating much here.

Also, I see so many guys not letting out a puff or two of air before a big descent. This would let out 10-20 psi which is fine as these psi will be refilled on the descent anyway. Yet 10 out 10 guys won't do this. And when I do it, they look at me like "what are you doing letting air out of your tire".
When Josh Poertner was at zipp, they did some work on this and found multiple failure modes - delamination was one. Melting the inner tube was another. They also found that a poor tire/rim interface due to manufacturing variances in tire diameter could lead to a possible failure mode if the increase in tube psi due to heat pushed the tire off the bead.

under these extreme conditions tubular tires can also fail. It happened on mass a few years ago at the tour of oman when high heat and a neutralized descent caused tubular glue to melt, sheering valves due to tire rotation...
 

·
Windrider (Stubborn)
Joined
·
22,021 Posts
I'm also very intrigued about the new Cosmic Carbon Pro SL clinchers!

One big feature is the claimed 200C degree brake track temp. This is 392F, which is a significant improvement over the current Tg of ~350F of today's highend carbon rims.

However, I would like to ask Mavic these questions:

1) why not make it 50mm deep?? I'll take aero gain over minuscule 30g weight gain any day!

2) what about anti-bite feature for the aluminum freebody? Or is the freebody made of ti?



Also, quoting Cyclingtips article above:



hmm I don't get the pricing.

1) shouldn't the rim version cost MORE than then disc version since more work has to be done on the rim version, e.g., treatment of the brake tracks for high heat resistance. This is great if you're a rim buyer, but I'd be asking why if I were a disc buyer.

2) Why is the disc version be higher than the rim version for UK folks?

3) Also for the UK, why is the Ksyrium cost more than the Cosmic? I'd think the Cosmic would cost more due to more material, but maybe the Kysrium costs more due to lower yield in the UK??

Anyway, the pricing seems to be most beneficial for US buyers of the Cosmic rim version, no? To conclude, I see weird pricing discrepancy regarding:
1) rim vs disk
2) Cosmic vs Ksyrium
3) for UK market
Pricing has nothing to do with amount of effort to build and everything to do with what people are willing to pay.
 

·
Registered
Joined
·
5,347 Posts
I'd avoid descending anything over 20% due to health and longevity factor, or go with aluminum rims. No issues whatsoever with aluminum on 20% for me.
This is why I ride aluminum rims for training- I live on a very steep road with many tight turns. I've had one tire failure on a carbon clincher from riding on my road before I stopped using CF rims here. The bead area overheated and the tire came apart at the bead. The rim was ok. I have seen this kind of failure one other time, on a team-mate's carbon wheel. I've stopped using those tires.

But setting a % grade limit is not directly addressing the problem, which is rim heat. A 20% grade with no turns, good sight lines and a flatter roll out at the bottom requires no braking, while a 12% grade with a 10 mph turn every 50-75 meters requires lots of braking and slow speeds. Braking adds heat to the rim and going slow means less heat is removed from the rim.
 

·
Registered
Joined
·
238 Posts
If you insist on carbon rims, think about tubeless tires and/or disc brakes. The latter obviously requires a new bike, but if you want to really be safe about carbon rims overheating, that'd eliminate the issue completely.
 
1 - 20 of 23 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top