Carbon Wheel Durability and Warranty

[MRC01]

What are your experiences with the durability and warranty service for carbon bicycle wheels?

My mountain bike has Reynolds Carbon AM 27.5 wheels. Over the years these wheels have failed me several times and proven less reliable than any other wheels I've had. I like their super light weight and short-term durability but their long-term durability has not been good. Next time they fail I'm considering wheels from a different manufacturer. But, maybe there's no point because all of them are like this? Or maybe the others are even worse?

The first time the rear wheel failed, it was because the pawls inside the rear hub that engage the freehub ratchet, sheared or rounded due to wear, failing to engage the ratchet, so pedaling didn't rotate the wheel. This is an unrecoverable failure that had me hiking out of the desert while pushing my bike. Some of the bikes in my garage I've owned for decades and tens of thousands of miles. I've worn out chains & sprockets but I've never seen a freehub internally fail like that. Neither had any of the bike shops in Moab. After I got home I reported this failure to Reynolds. They said these hub internals are "consumables" and I had to buy (not covered under warranty) a freehub rebuild package that included new pawls & ratchet. This fixed the hub.

The second time the rear wheel failed, the carbon in the rim delaminated and structurally failed. The wheel was not crashed and only plastic tire irons have ever been used. Reynolds admits this was a manufacturing defect and covers this under their "lifetime warranty" (I use that term loosely) by replacing the rim for free, and charging $150 to rebuild your old hub into a new rim. With a 6 week turnaround time. I told them I will build the wheel myself so they simply mailed me a new rim. Since they don't make my rims anymore they sent me their closest fit which has different ERD so I'll need new spokes. No big deal, just another $50.

Meanwhile, my other bikes that have metal wheels/rims have never had failures like this, despite thousands of miles and decades of use. So are all of these high end carbon wheels simply not built for long term durability, made to be as light as possible and last a couple of years until the warranty expires? Or are there some that stand the test of time? And is the warranty service from other companies different (better or worse) than Reynolds? I'm not trying to throw Reynolds under the bus, but just trying to get an idea how their durability & service compares with others.

 

[wwillson]

I have a friend who rides between 10,000-20,000 miles/year and has ridden a bicycle over 1,000,000 miles. He's tried several brands of carbon wheels and because they always crack, he only rides on alloy wheels. I bought a TitanFlex road bike from him with about 100,000 miles on the frame and wheels. The frame finally cracked at 110,000 miles, but the DT Swiss alloy wheels are still going strong.

 

[IndyIan]

Maybe try these ones? I guess its fun to have the "best" stuff but unless I really improve my riding I can't see me getting carbon anything. Cost benefit isn't there, I am an aluminum level rider!

 

[MRC01]

I have a friend who rides between 10,000-20,000 miles/year and has ridden a bicycle over 1,000,000 miles. He's tried several brands of carbon wheels and because they always crack, he only rides on alloy wheels. ...

Sounds like he's had the same experience I had, and he had it across several different brands. That's useful info.

...
Maybe try these ones? [video of destructive testing of Santa Cruz carbon wheels]

That video demonstrates it perfectly. Carbon wheels have excellent short-term durability; they handle just about anything you throw at them. But their long-term durability is what seems compromised; however strong they are, eventually they crack or fail with age.

This is all a bit disappointing because I really love those carbon wheels right up to the point where they completely failed. I suppose I can consider a carbon rim like a consumable, rebuilding it every few years when it fails and gets replaced under lifetime warranty. As long as it doesn't fail catastrophically when I'm riding it.

 

[MRC01]

To close the story, the warranty replacement rim arrived the day before the ride (Blacklabel 287). I rebuilt the wheel that same afternoon and rode it on the OTGG, 350 miles of rough terrain with 30,000' of climbing over 5 days. It's still round & true. Very strong. Kudos to Reynolds for coming through just in time.

Problem is, the front wheel, which is still original, just popped yet another spoke nipple. These Al-alloy spoke nipples just don't last on these carbon mountain bike wheels. Reynolds should be using brass nipples which are much stronger. They add 20 grams to the wheel which is nothing compared to the 800 gram tires we typically use.

 

[Brons2]

This is all a bit disappointing because I really love those carbon wheels right up to the point where they completely failed. I suppose I can consider a carbon rim like a consumable, rebuilding it every few years when it fails and gets replaced under lifetime warranty. As long as it doesn't fail catastrophically when I'm riding it.

I've cracked just about every aluminum back wheel that I have, being 6'7" and around 300 lbs. I now rebuild them after 5 years regardless of condition, they will almost always have cracks emanating from the spoke holes at least starting. I don't buy lightweight rims anymore either, nothing under 550 grams or so.

 

[MRC01]

I weigh about 175 and I've never cracked a rim in nearly 40 years of avid cycling. Back in the 80s I had wheels that were too light and had to be re-trued after aggressive hill climbing, but never cracked. I've got a couple of bikes with 20,000+ miles on them, wheels are fine. This wheel cracking stuff is new to me, kinda scary as there are moments where if the wheel fails when riding it could be fatal. We trust our lives to our wheels.

 

[Pablo]

My bike came with Crank Bros Synthesis CF rims. I am hoping they last, any opinion on these: https://www.crankbrothers.com/products/synthesis-e-carbon-wheelset?variant=12449373913184

 

[zzyzzx]

After reading this thread, I would avoid buying anything with carbon rims.

 

[Surestick]

You can't blame the freehub failure on the carbon rims.
Wheels on anything other than a non-rim brake equipped road bike (and I guess anything with steel rims) are consumables.

I think there's a tendency to blame the carbon for rim failure on carbon wheels and just shrug and say "that's life" when we damage aluminium rims.
The failure modes can be different but, on the whole, there doesn't seem to be a deluge of carbon rim failures. Carbon seems to stand up to more abuse then fail completely, aluminium will get dings from rocks, or go out of true from events that carbon would shrug off. The aluminium rim will likely still be rideable to get you out of the woods but might need replacing.

Out of curiosity, was the delamination failure something that could have been caught by a pre-ride inspection (not blaming, I think we all pretty much just check tire pressure, hop on, and ride) or was it sudden or hidden (on the rim bed where it was hidden by the tire or something)?

 

[Pablo]

After researching, talking with others, the industry and bike shops and yes I know all anecdotal - HARD riding - I am very confident in my CF wheels. They are well made, with brass nipples, light weight and strong. If something about my thoughts change I will post up.

 

[MRC01]

... The failure modes can be different but, on the whole, there doesn't seem to be a deluge of carbon rim failures. Carbon seems to stand up to more abuse then fail completely ...
Out of curiosity, was the delamination failure something that could have been caught by a pre-ride inspection (not blaming, I think we all pretty much just check tire pressure, hop on, and ride) or was it sudden or hidden (on the rim bed where it was hidden by the tire or something)?

I agree carbon rims are VERY stiff and strong, stiffer and stronger than metal. But when they fail they fail completely. If you build them with brass spoke nipples, they should last a lifetime. Manufacturers should not be using Al-alloy nipples because eventually, those spoke nipples *will* corrode and crack due to redox related issues. I rebuilt both my wheels using brass nipples and they should be good for life now.

I'm not sure when the rim started delaminating, but I noticed it after a ride, a "spur" on the outside side of the rim. Fortunately, it didn't break while riding.

Of course, the freehub failure is unrelated to carbon. It is a symptom of the race to the lightest at any cost. They could have made those pawls from steel instead of aluminum alloy and the freehub would last a lifetime. But that would be a few grams heavier!

 

[Cujet]

From a very basic engineering point of view, carbon fiber composites are subject to sudden yield failures. Contrast that with properly chosen metals that may dent, deform, stretch or otherwise remain partially intact.

One aviation company that builds composite airframes uses a Carbon structure-single fiberglass layer-Carbon structure configuration to eliminate delamination. In other words, where ever 2 carbon parts are bonded there is a thin interface of fiberglass cloth. The method works very well on carbon propeller blades (and airframes) and has eliminated the previous structural problems. The use of Kevlar wound into the carbon has reduced the sudden failures and improved crash strength at the expense of being mildly hygroscopic (exposed Kevlar can absorb moisture, such as where impact damage occurs), this can lead to more difficult repairs of carbon/kevlar blends.

In the end, newer tech is not necessarily better. Although I am infirm now, I still have my Titanium Cyclocross bike, with Mavic alloy wheels and stainless spokes. 44,000 miles of troublefree use and only one major crash. If I were made young again, I'd still choose metal components for my bicycle.

 

[MRC01]

... I still have my Titanium Cyclocross bike, with Mavic alloy wheels and stainless spokes. 44,000 miles of troublefree use and only one major crash. If I were made young again, I'd still choose metal components for my bicycle.

My road bike is a 1999 Trek 2200, all original except I've replaced the chain, sprockets, tires, brake pads. I've put at least 20,000 miles on it. All bearings serviced but still original. Runs better than new. Aluminum can develop stress fractures over time, but this frame has not. It will probably last forever.

 

[Cujet]

My road bike is a 1999 Trek 2200, all original except I've replaced the chain, sprockets, tires, brake pads. I've put at least 20,000 miles on it. All bearings serviced but still original. Runs better than new. Aluminum can develop stress fractures over time, but this frame has not. It will probably last forever.

Yes, aluminum has a finite fatigue life, much shorter than the fatigue life of quality steel. Much of it depends on the alloy chosen and the severity of the cycles it's subject to. It's why there are comparatively few aluminum springs. Also why aluminum aircraft generally have an hourly life limit. Strangely, aluminum grows weaker with each severe cycle. An interesting benefit to aluminum is it's stiffness related to it's tensile strength. Put another way, for a given load, aluminum is considerably thicker than steel, so will exhibit greater stiffness. This makes it great for aircraft use.

 

[MRC01]

Yes, aluminum has a finite fatigue life, much shorter than the fatigue life of quality steel. Much of it depends on the alloy chosen and the severity of the cycles it's subject to. It's why there are comparatively few aluminum springs. Also why aluminum aircraft generally have an hourly life limit. Strangely, aluminum grows weaker with each severe cycle. An interesting benefit to aluminum is it's stiffness related to it's tensile strength. Put another way, for a given load, aluminum is considerably thicker than steel, so will exhibit greater stiffness. This makes it great for aircraft use.

In bicycles, they must use oversized tubing with aluminum frames, which makes them very rigid. That's great for efficiency, not so great for comfort. You may enjoy reading this bicycle frame strength/durability test: https://www.sheldonbrown.com/rinard/frame_fatigue_test.htm

It's several years old, but the analysis is still relevant. Interestingly, the only 3 frames that did not fail were aluminum & carbon. All the steel & titanium frames failed. Just goes to show, the design and build method & quality are even more important than materials when it comes to the frame's character and durability.

 

[y_p_w]

In the end, newer tech is not necessarily better. Although I am infirm now, I still have my Titanium Cyclocross bike, with Mavic alloy wheels and stainless spokes. 44,000 miles of troublefree use and only one major crash. If I were made young again, I'd still choose metal components for my bicycle.

If one is just riding, a traditional hand-built steel frame with Columbus SL tubing would be fine. Does anyone really get more fun out of a super-stiff competition style frame?

Back when I was doing this I tried doing stuff to lighten up. I bought some tubular rims but never actually used them. I also tried using aluminum nipples and ended up stripping a few, while I never had to be careful with brass. Latex tubes were a real pain having to pump up all the time. I had a shop show me a super-light bike that tipped in at about 17 lbs on the scale back in the early 90s. I think by then, top teams in the big bike races still had bikes in about the 23 lb range. They didn't care that much about shaving every last ounce.

 

[y_p_w]

In bicycles, they must use oversized tubing with aluminum frames, which makes them very rigid. That's great for efficiency, not so great for comfort. You may enjoy reading this bicycle frame strength/durability test: https://www.sheldonbrown.com/rinard/frame_fatigue_test.htm

It's several years old, but the analysis is still relevant. Interestingly, the only 3 frames that did not fail were aluminum & carbon. All the steel & titanium frames failed. Just goes to show, the design and build method & quality are even more important than materials when it comes to the frame's character and durability.

Back when I was into bikes, I remember the Vitus 979 aluminum frame. I remember hearing about Cannondale's entry using oversized but thinner tubes to gain stiffness. I though the Vitus aluminum frame flexed a ton since it was still about the same 1" tubing as most steel frames of the time. I think the tubes were also glued into the lugs.

 

[MRC01]

Back when I was into bikes, I remember the Vitus 979 aluminum frame. I remember hearing about Cannondale's entry using oversized but thinner tubes to gain stiffness. I though the Vitus aluminum frame flexed a ton since it was still about the same 1" tubing as most steel frames of the time. I think the tubes were also glued into the lugs.

I had one of those! Back in the 1980s my endurance race bike was a Vitus 979 with Campy Super Record. It was a flexy frame, but very light and comfortable on endurance rides. It was indeed glued together, similar method to what Lotus used in aluminum car frames. I put thousands of miles on that bike. That was a strong frame and survived a 40 mph crash.

My latex tubes leak down about 15% in 24 hours. Butyl and tubeless don't hold air perfectly either. Because of this, serious riders pump their tires before every ride, to know the pressure is exactly right. If you check tires before every ride anyway, latex tubes aren't any more hassle than butyl. And they are just a small bit smoother and faster.

 

[y_p_w]

I had one of those! Back in the 1980s my endurance race bike was a Vitus 979 with Campy Super Record. It was a flexy frame, but very light and comfortable on endurance rides. It was indeed glued together, similar method to what Lotus used in aluminum car frames. I put thousands of miles on that bike. That was a strong frame and survived a 40 mph crash.

My latex tubes leak down about 15% in 24 hours. Butyl and tubeless don't hold air perfectly either. Because of this, serious riders pump their tires before every ride, to know the pressure is exactly right. If you check tires before every ride anyway, latex tubes aren't any more hassle than butyl. And they are just a small bit smoother and faster.

Well - I wasn't sure about how durable the frame was, but of course having the glued in frame wasn't unusual. One of my riding buddies had a Specialized carbon fiber frame with the tubes glued into beefy looking aluminum lugs. My primary bike was a traditional Bottechia frame with Columbus SL tubing. Once I was at a bike shop looking around for something new, and the sales guy was telling me that he wouldn't recommend anything but traditional steel. His rationale was that for just recreational riding, it was comfortable, durable, and easy to fix. He claimed that if a section of the tubing was damaged, it could be replaced by cutting out the damaged section and welding in a replacement piece. I'm not sure that would have been worth it for a $500 frame though.

I think the 80s and early 90s were the birth of technologies we see today. I believe the Kestrel 4000 was the start of the monocoque carbon fiber frame on road bikes. Wonder what happened to the Trimble X-Frame mountain bike frame. There were of course those Huffy off-offs custom made for US Cycling. I heard they were actually made by Huffy and cost something like $50,000 each in 1980s dollars. Of course they weren't the same as the relabelled Serotta frames that carried the Huffy or Murray name. Somehow this composite photos shows all of them.