Tunnelrat81

One of the local club guys was on a slow-moderate ride with a group and his carbon fork just came apart. Not sure where the breaking point was, but it put him into the ground. They warrantied the entire frame for him, but still. No stick, possibly a pothole or bump, but he claimed that he hadn't hit anything hard at the time of the failure. It does happen...just not very often at all.

-Jeremy

island rider

See, this is the thing. I'm reasonably certain that it doesn't. The issue is just that the signals of the underlying problem which lead to the fork coming apart were not recognized. Even if it was a new sound or vibration, if not a crack or paint bubble, I would bet there was an indication that was simply missed through no fault of the rider.

grolby

I remember that too, though it was more like four years ago. As I recall, it did NOT end well - the victim ultimately died from his injuries.

That's definitely a manufacturing defect, of course, and that's not how these things usually go. A major tragedy.

alexfboyle

https://www.bustedcarbon.com/
There are some JRA stories on there. Most are crash related though.

Tunnelrat81

I agree that there must have been some kind of indication. The most I ever heard about it was that he did in fact remember a creaking noise for some time before the failure, a creak that he hadn't been able to track down yet, but had no other indication. And this begs the next question, how many people with small 'creaks' are there in your group rides. There are lots in mine. With >50 different parts of a bike (carbon fiber frames or any any other) that can emit very similar creaking sounds, and with the fact that the integrity of carbon fiber can rarely be checked visually (without the aid of x-ray testing), if the only 'warning sign' of an impending failure is creaking... I'm not encouraged.

Again, I'm not in any way arguing that carbon fiber exploding is common or even something worth considering...just that it seems to have happened on rare occasions, one of which happened to be in my community.

I'll say that I don't know the rider very well, and don't know what kind of abuse or lack there-of had occurred before the failure. I don't know his maintenance practices or inspection habits. I'm pretty certain I heard that he hadn't ever crashed the frame (it was one of my first questions). A close friend who I've ridden thousands of miles with was with him on the group ride when it happened, and helped him through the warranty process to get his new frame etc.. The little that I know about the incident I heard from him.

-Jeremy

Reynolds 

I've seen a CF frame broken in two at DT and TT at a race crash with another bicycle.

StephenH

One of my fellow riders tells of going through 4 carbon fiber frames before switching to titanium. I think all were cracks, though, didn't cause wrecks or happen in wrecks. First three times, frame was replaced under warranty, last time, they wanted $1000 to upgrade under warranty and he bailed. He now has a considerable collection of titanium bikes.

island rider

I think you initial point is the right one. There is always an indication, the question is whether or not it gets caught in time. That indication can start at mile 1 of a century and by mile 80 become a full blown problem, and have you rolling in on your face at mile 100 though, so it pays to be as attentive as you can.

sdvictor

My cervelo R3 is being warrantied at this time, and only because I inspect and clean my bike once every 2-3 weeks (ride 6 days a week), I checked for cracks and discoloration and saw some. Brought it to a Cervelo dealer and they RMAed it, and said that I caught it early on. They agree that people should be doing this, because they see quite a few frame failures on all brands of all bikes of all types; and they typically exhibited obvious signs that were overlooked or ignored.

Velo Dog

I've seen a carbon fork fail suddenly, on a moderately rough road. And a neighbor of mine, at least 20 years ago, was an aeronautical engineer heading a testing program for CF fuselage parts. One of their programs required testing to failure, stressing the parts until they broke. CF was many times stronger than whatever they were using (probably aluminum, I imagine), but when it failed, it went all at once, no perceptible warning at all. Newer materials may be different, though.

merlinextraligh

That was obviously a huge tragedy.

The fortunate thing is that it's the one incident that everybody here remembers. And we remember it not only because of the tragedy, but because how rare it is.

merlinextraligh

I've seen some manufacturers of CF parts touting the addition of other materials (kevlar was one) purporting to make failures less sudden and catstrophic. Seems like a good idea if it works.

Willier is putting a film in their CF layup that's supposed to make it less subject to impact damage. I would think it might also make failures happen less suddenly.

sbxx1985 

Wasn't there a thread about a Specialized failure a year or two ago? It was the guy's daughter's bike during a group ride, or something like that. The pictures were incredible.

Please hold.

Menel

Aren't there several counts of carbon spokes in Mavic wheels doing this?

sbxx1985 

Here it is.

https://www.bikeforums.net/showthread...+frame+failure

Phantoj

Ran into a parked car and the frame broke. Not what I would call a "failure".

RT

Must be done.

EdIsMe

A buddy of mine hit the ground at 30mph on his Specialized Tarmac SL2, frame snapped in 3 places.

Obviously not a JRA though...

There's video of the crash: https://www.youtube.com/watch?v=1DeMDGqptu8
He's wearing the orange jersey. I'm off to the right of Mr. Cameraman.

sbxx1985 

Try again. Reading aloud helps.

merlinextraligh

Read the thread as well, and I know what the girl reported. However, the manner of failure is completely consistent with hitting something.

For example Caloso's bike failed in the same manner whe hit hit the curb.

Gazillion steel bikes have buckled tubes in that area after the bike ran into something.

It's possible the hard brake event caused a frame weak from a mechanical defect to fail.

However, given the number of warranty claims where the owner was JRA... I'm skeptical.

None of us having witnessed it, we'll never know for sure.

sbxx1985 

I was skeptical as well. It didn't add up. The OP addressed it here, but I wasn't there, so who knows.

Regardless, I don't subscribe to the assploding carbon nonsense. I have the bottom 8" of my Enve post on my desk at the office. We use it as a hammer.

island rider

The issue with this is that you would have expected some other type of damage as well, wouldn't you? Caloso, how was your front wheel after the crash?

I could imagine this happening in enough of a panic stop. I.e., shut down the bike's momentum via the front wheel and the energy has to go somewhere. The same net effect as hitting a curb. It doesn't matter what tops the front wheel, just that it stops.

That said, if a panic stop will shatter a frame, there are issues there.

caloso

Tire was flat and rim was bent, but the LBS was able to straighten the rim and true the wheel. I'm still riding them as a commuting/training wheels--in fact I rode them to work today and will ride them in a training crit after work. 2006 Ksryium SL SSC, in case you're interested.

Phantoj

whoops... I just scanned the first post and quit when I saw "looked up... a parked car"...

island rider

That's what I thought. If the girl's wheel and fork were fine I would think her story rings true.