Have any Clydes had firsthand experience with a carbon fiber component failure?
 

I was reading a thread in another forum where the OP was basically stating carbon fiber bikes will explode while you ride them and throw you to the ground. I'd never heard of that happening in a recreational rider situation.

I'd like to find out if any of our Clyde's have firsthand experience with a failing carbon fiber component during a ride? If so, what were the specifics? What part, brand, how old, how many miles, how was it ridden, was it crashed before the failure? Thanks in advance.

My experience. I've put about 1200 miles on a carbon fork and seat post so far with no issues.

The OP in that other thread is what is technically known as a silly goose.

You spelled "asplode" incorrectly.

Bikes of all materials break. I love how worked up people get about carbon frames - if you ask me, the most worrisome part that could catastrophically fail is the fork and (drum roll) good luck finding a bike without a carbon fork these days. Low end Al bikes and some high end steel bikes lack them but the rest of us are pedaling away with carbon all over the place.

Way back in the early 90s I went bike shopping with a friend and we ended up at a specialized store - they were selling a lugged carbon round-tube bike (Allez at the time, I think) and the sales guy had a sample of the carbon tubing to use as a prop. He took that thing and WHACKED the table about as hard as he could to demonstrate that carbon wasn't some frail material. I don't know what that tells you about the longevity of a carbon frame, but it was pretty impressive. :D

I saw in another thread where some REI aluminum framed bikes broke while being ridden, at least one anyway, and it threw the rider to the ground :-).

Solid Forged TI (not tubing, solid metal) is probably the only bike that would never break in a million years and a billion units :-).

Anything built to convey a human down the road and sharing the road with cars, trucks, and other stuff probably has a wide safety margin.

Bill

"probably has a wide safety margin"

probably being the key word. I have found, as a clyde, that I have reached the safety margin with nearly all of my bicycle components. The issue with carbon fibre (and Ti, and Al) is not that it is inherently weaker, but when you reach the safety margin, it breaks catastrophically, not slowly like steel. Technically, you want something that is ductile, with a yield strength (point at which it bends) is much lower than the ultimate strength (point at which it breaks). With a steel bike (or fork), if your too heavy, it will bend and gently let you know to "please get off me", carbon, Al and I believe Ti are not very ductile, and so will snap before you know there is a problem. This is what makes them scary for me. I ride an all steel bike, including a steel fork. I sometimes wonder if I am in idiot for doing so, since EVERYONE else is on carbon, but this is just a test of the common query, "if everyone jumped off a cliff...." I get to thinking I should try carbon, and then my Al crank cracks or something ridiculous and I am again reminded that bicycle engineers are for some reason unable to fathom the existance of riders who weigh more than 180lbs. (I am 250lbs)

You don't need the frame to break to be thrown to the ground. I've had it happen several times on my mountain bike and the bike was just fine, me not so much.

I have never broken a carbon component. I have watched a rider come to grief when his carbon seatpost snapped when he was in front of me on a descent at over 30 mph. It was spectacularly horrible but, miraculously, he sustained only bruising and a broken thumb.

Oh, and I doubt if he weighed more than 150 lbs.

Stuff breaks. Titanium breaks, steel breaks, aluminium breaks. It makes sense to stay within the specified parameters for whatever one rides, but carbon is no more intrinscially liable to failure than any of the other materials.

I once upon a time was driving a truck that was placed out of service for 13 different frame cracks (first year driving). Steel breaks. I have broken tools made from a variety of steels, knives, screw drivers, sockets, shovels, saw blades, etc. Then there are the numbers of bolts I have broken. The most common problem clydes seem to have with breaking on a bike are spokes and those are made from steel.

Broken two carbon parts...

Seat Post
I traveled with my bike a couple times. Unbeknownst to me, I had over-tightened the carbon seat post after re-assembling my bike (in bike box for flight) and created a pinch in it. It finally failed while I was riding. It failed slowly over about 20-minutes when I finally noticed it. At first, it felt like something was wrong with my saddle. I had broken saddles before and thought it was recurring. I visually inspected the saddle, found nothing, but never thought of the seat post. As I rode, I realized the saddle was rocking backwards. I finally found the problem in the seat post. It had cracked and exposed fibers fraying. It was still attached for awhile until I pulled it off. I never crashed.

Frame
Bike developed an issue where the chain was rubbing the front derailleur cage. At first, I thought it was a bent chain ring, so I tried bending back, but the rubbing continued. Over about a month, I continued riding and being annoyed by the rubbing (I regularly ride 800-1,000 miles per month). One day while cleaning the bike, I noticed a small crack on the chainstay bridge behind the bottom bracket. I figured: bottom bracket area, lots of twisting, must be paint crack, so I ignored it. One day, while riding, I had just turned last corner to my house, about 50m away. I stood up as I gently pedaled in. Suddenly, my chain fell off and I lurched, but didn't fall. Son (with me at time) and I looked at eachother. I stopped, put the chain back on and started going again. As I sat on the saddle, I immediately felt the frame flexing unnaturally in the middle, like some sort of shock-absorber. I hopped off. The small "paint crack" I had noticed earlier that month had expanded into an 8-inch long crack, circling from behind the BB, over its top, down and up the belly of the down tube. I could see the fibers sticking out from the crack. Frame can be repaired, but I haven't the funds to do so.

Could it have been worse? Sure. Could have happened when I was contesting a sprint at 40mph or downhill at 45. But, in either case, I never hit the ground when two supporting components failed.

I don't ride that much any more. But at my peak it was over 5000 miles a year.

I think my carbon fiber bike is old enough to drink.

No problems, well save that there are now more gears and parts are not available for the groupo. It may not be all that long until I have to decide if a new bike is in order.

Never under 210 when riding, mostly 220 and over. So I'm not a barely clyde.

true, though I think steel is still less prone to sudden catastrophic failure. I have bent three forks in my day (on older mountain bikes), and I was very happy they bent rather than snapped. I keep thinking about those forks when I consider carbon or Al forks.

I snapped some carbon seat rails on a Fizik saddle..

Even if the "failure mode" for CF is potentially worse, a well made CF fork is gonna be stronger than a well made steel fork of similar type (ie: weight weenie, robust, etc)

I have well over 50k miles on one carbon frame and fork w/o failure but it is not a ridiculously vapor light frame.

On the other hand I have had aluminum and also titanium parts break and even steel (frame, axles, pedal, etc) break. Go figure.

I know more people who have had problems with aluminum than carbon fiber...

In 2009, I sold a carbon frame that I purchased in 1994. As far as the buyer and I could tell, the frame was as solid as the day it was purchased.

My current carbon fiber frame (2008 Cervelo RS) has almost 15,000 miles on it. I've been hit at low speed by cars twice and the frame is undamaged as are the carbon fiber fork and handlebars. This frame feels much more solid than the one from 1994, so I expect that it will last just as long if not longer!

I though discussion of carbon failure modes was reserved for February out of respect for the Northern Hemisphere winter and subsequent Bike Forums patterns.

While this didn't happen to me directly, it did happen to a riding mate of mine, with plenty of corroberating witnesses:

Whilst on the final straight bit of road leading to our club's meeting place, he stood up to particpate in the sprint to the club house. A few pedal strokes later his carbon, Look 695 broke across both the top and down tubes sending him head first into the pavement. It is no entirely known if the bike had been previously crashed or damaged. Some debate has taken place about what constitutes a "crash" and how exactly one would recognize damage that might effect the bike in the future and the fact that he had been transporting a very light frame on a bumper hitch rack, supported by the top tube.

Although one or the other tube probably failed first, they failed so quickly that for all intent and purpose everyone is viewing them as having failed together. Look offered him another frame. I believe he declined.

A year since the incident and he still has not fully recovered. Although he is back on the bike he can't train. He has to moderate is efforts or he will suffer debilitating headaches that can put him in bed for days to follow. He's back working. But, again, has to be careful about how hard and occassionaly has to take time off.


This isn't the only carbon part failure I have person knowledge of. I have another regular riding mate, who's rear derailleur mount broke off from nothing more than the bike falling over. Trek advised that this was not repairable and the frame was out of warrantee. He managed to epoxy and fiberglass it back together close enough to aligned that the derailleur still works.

Carbon can fail. As can any other material. And, yes, carbon's failure mode can be more catastrophic than other materials.

Clydes just shouldn't buy really light components, regardless of material.

As a rider of steel bikes I'm duty bound to weigh in here with opinions and anecdotal evidence. Assploding CF frames get a lot of play, let one break in South Africa and there will be a thread about it on BF. Other than in a race, I've never seen a CF failure. Go to a group ride and see how old some of the CF frames are, I don't see much difference between long term wear of CF and other materials.

psst: Don't tell anybody, but I have a CF fork and seat post on my steel bike

Do you know how old it was? How many miles?

Is it bad to hang it by the top tube? I've got my Roubaix hanging by the top tube in the garage. No banging around on the hanger, I just gently set it up there after each ride. I transport it in the back of my track standing up on it's wheels in a bed rack.

Is a Roubaix frame/fork considered a light component?

Oh no you di'int!

Steel is real... rusty. :lol:

Jarrett- don't clamp your frame in a stand but suspending it should be fine. I actually have a hitch rack for my truck and I strap the roubaix in that thing without worrying about anything other than scratching the finish.

Do things break? Yes. Can you predict it ? No. Does this bother you so much you are afraid to ride a particular bike or material? Don't.

I have seen Carbon go through a "catastrophic failure" once, right in front of me. A Cannondale super 6 evo, while my buddy was standing to climb. He's built like a sprinter, and rides hard. The non-drive seat stay snapped in two, about 5 cm above the drop-out. Made a very loud noise. Cannondale sent him a new frame, which he sold. He's on a Venge now.

I personally cracked an aluminum frame, near the BB.

I've never hurt steel (both main bikes are Italian steel now), nor have I seen it damaged except by crashing into things (which will damage anything).

My trepidation on carbon is not based on a fear of it somehow being more prone to breakage while riding. I just don't think it is, and I'd say 90% of my riding buds are on carbon. It's based on two things: first, it can break in a big way when it does, which could contribute to harm to me (not likely, and wouldn't stop me from getting one); second, it is known to be weakened by stuff that happens to bikes (like the kid knocking it over, or the fork being dinged, etc.) because it is designed for great strength in one vector (where the forces are applied whine riding) but not necessarily in another.

If (and maybe when) I own a carbon bike, I will be much more careful with it, and I treat my steel rides very well.

I've had one seatpost crack on me, right at the seat tube/collar. Probably a combination of overtightening by the owner and more than a few really rough potholes. And 5 years. I think it was mostly the overtightening.

Any material can have flaws from the creation process. I have seen some really expensive machined parts be scrapped during the mfg process because cracks were discovered, and that was "billet" 4140 steel from a good maker.

But I still say the average carbon, or steel, or aluminum frame would be designed to take any normal road stress with TWICE the maximum weight rating loaded onto the bike.....too much bad press when a frame fails and the rider is hurt or killed due to the failure. Nobody will ever forget those REI frames failed, or that they tried to slough the responsibility for that off onto the people who make frames for them.

Bill

There's nothing wrong with transporting a CF bike by the seat tube. I do it all the time on my hitch mounted rack, although I do wrap the top tube in foam to prevent any issues. CF is nowhere near fragile enough that hanging it off a hitch rack will cause you any trouble. It's also generally not nearly as susceptible to fatigue as most metals. That's why you have modern jet airliners made from composites and not aluminum. Aluminum wouldn't hold up as well in tropical climates and other harsh conditions, but a composite frame fareas much better.