Bicycle Mechanics - Crashed the Carbon Fiber Frame....what now?

I jinked this evening and tapped my riding buddies front wheel....down he went at 18-20mph. Aside from his shorts and hip, a fork blade and a portion of his top tube got seriously scuffed. I saw no cracks or penetration. Question: Though an accident, I feel badly.......I'm unfamiliar with cf-- have I shortened the life of his frame or begun a process leading to a future frame failure?

Internal stress is very hard to detect, but if there is any bulging, chipping, or alignment issues, just make sure your friend mentions is to the mechanics the next few times he goes in for a tuneup.

Your friend was too close...it wasn't your problem...unless you braked suddenly and swerved. Tell him a little prayer before each ride might help.

You can only protect your front wheel, as long as you didn't brake or slow quickly there is nothing you could do about this. Inspect the frame closely, but CF doesn't really flex and fatigue it fails. So if you don't see any penetration of of the fibers or unusual flexing due to a crack the frame is most likely Ok. Trek use to have a film clip on their website on how to inspect a CF frame, you may want to see if it is still there.

Be very careful riding that frame, if you can't check it out get it to someone who can.

I crashed a Giant TCR in a crit last spring. I inspected that sucker completely, only finding a very small chip in the top tube's clearcoat. The handlebar had smacked it when my wheel got taken out by a downed rider. Aside from a broken bone in my wrist and a bruised shoulder I was stoked my bike was fine. So I ride it for two more weeks then go to clean it after a ride only to discover two 1 inch long cracks in the top tube. Bye bye frame.

Steel isn't dead it is just sleeping until the cycling public comes to its senses.
I just crashed heavily on my new Mondonico Daimond Extra Columbus Neuron tubeset with an older Pinarello steel fork. Had is checked out and needed the derailluer hanger coldset. No worries...and the bike is 17.8 lbs. There are some good and light steel frames still being built.

Id tell your friend to get a bike thats not "plastic"

Id tell your friend to get a bike thats not "plastic"

Yeah, an AL or Steel frame never gets damaged in a crash:rolleyes:

Be very careful riding that frame, if you can't check it out get it to someone who can.

I crashed a Giant TCR in a crit last spring. I inspected that sucker completely, only finding a very small chip in the top tube's clearcoat. The handlebar had smacked it when my wheel got taken out by a downed rider. Aside from a broken bone in my wrist and a bruised shoulder I was stoked my bike was fine. So I ride it for two more weeks then go to clean it after a ride only to discover two 1 inch long cracks in the top tube. Bye bye frame.

While I get your point on careful and repeated inspection, Calfee could probably repair that frame for cheap (much less than replacing a top tube on a steel bike).

Ride Ti. The good ones are very light, and you can be confident about crash survival.

Yeah, an AL or Steel frame never gets damaged in a crash:rolleyes:

its usually alot more obvious when a steel or AL frame is damaged. I just look at it as a safey aspect.

its usually alot more obvious when a steel or AL frame is damaged. I just look at it as a safey aspect.


Can't get more obvious than this. :eek: Carbon frame.

A friend of mine was broadsided by a car at 40mph. He was not seriously injured. Wow! :eek:

Jeez... it seems I'll never regret never having or wanting to have any CF part on my bikes, let alone the frame... There just never seems to be anything appealing about it, and a whole lot of appaling against.


EDIT: seriously, what's the appeal of CF? As someone already said, there are pretty light steel frames, not to speak of Ti. Is it the 300-400g less of weight? Take a dump and there you go - instant CF weight class you and your bike together.
I guess it's the higher price. The stupid "it's expensive, it's GOTTA be good."-mentality. Followed by cognitive dissonance "I invested too much money into this thing, I must defend it at all costs - this thing IS good otherwise I feel stupid".

In aerospace, there is actually a "coin tap" test for damaged composite structure. Take a quarter or larger coin and gently tap the area around the scuffs. It should all sound the same. If it makes a different sound anywhere near the damage, you could have internal delaminations that might cause failure.

I love my steel Serotta...

Jim

EDIT: seriously, what's the appeal of CF? As someone already said, there are pretty light steel frames, not to speak of Ti. Is it the 300-400g less of weight? Take a dump and there you go - instant CF weight class you and your bike together.
I guess it's the higher price. The stupid "it's expensive, it's GOTTA be good."-mentality. Followed by cognitive dissonance "I invested too much money into this thing, I must defend it at all costs - this thing IS good otherwise I feel stupid".

You want a serious answer? Well, there really isn't too much of an advantage for CF, but the slight advantage appeals to some. People tend to believe that "road vibrations" are reduced with CF, although a well made aluminum frame can have the same effect. I think it's supposed to be stiffer, or at least the molding process can vary the stiffness around the frame, hence the ubiquitous phrase "laterally stiff yet vertically compliant". The moldabality of the material also helps make parts more aerodynamic, which really doesn't do much anyway because 90% of drag comes from the rider's body. But it is more attractive. And on average, carbon fiber frames can be easily made more lightweight than other materials.

Will 80% of riders notice or appreciate the difference? No, but certain time trialists and triathletes think that spending the $$$$ on lighter and more aero gear to improve their times is easier than training. Not to mention weekend warriors, :p. That said, I think CF has its place in cycling. A CF fork on a metal frame might save the rest of the frame in a crash because it fails quicker. This is somewhat important if your metal frame is very valuable. Having a CF fork and stem makes a big difference on certain aluminum bikes that ride harshly. I know, I ride an old Al C'dale R500 that has straight seatstays, non-ovalized tubes, and an Al fork. Can I still ride it? Yes, but I tend to think a CF fork would make it at least slightly more comfortable. Also, if you want to build an extremely stiff frame, as are valued in track racing, CF is a decent choice because you can get thick tube walls without increasing weight too much.

Just some thoughts :p

A CF fork on a metal frame might save the rest of the frame in a crash because it fails quicker. This is somewhat important if your metal frame is very valuable. Having a CF fork and stem makes a big difference on certain aluminum bikes that ride harshly. I know, I ride an old Al C'dale R500 that has straight seatstays, non-ovalized tubes, and an Al fork. Can I still ride it? Yes, but I tend to think a CF fork would make it at least slightly more comfortable. Also, if you want to build an extremely stiff frame, as are valued in track racing, CF is a decent choice because you can get thick tube walls without increasing weight too much.

Interesting points. But this one I quote, is kinda... funny. A carbon fork is better because it will fail quicker? A big WTF to that. I mean, if your front wheel goes, you go - down. And having your front fork fail kinda affects the position of the front wheel...

Regarding lightness: as I already said, visit the loo and there goes the difference in weight.


That said, I can aprecciate the things you discuss, as a point of view CF cyclists might have.


By the way, I really do notice the (only) Al-framed bike I have (now somewhat dismantled) rides more harshly than any of my steel framed bikes. Yes, I know tyres make the biggest difference, but I'm talking at parity of tyres.

Regarding lightness: as I already said, visit the loo and there goes the difference in weight.


.


Maybe they are made for riders who like to ride around having to poo and dont want to carry the extra weight of the poo it self. :rolleyes:

Maybe they are made for riders who like to ride around having to poo and dont want to carry the extra weight of the poo it self. :rolleyes:

Not quite sure what you mean; are you saying they're basically anal-retentive?

Just saying that for thousands of extra dollars, you dont even have to make sure you poo before you ride your bike to loss an extra pound!

Interesting points. But this one I quote, is kinda... funny. A carbon fork is better because it will fail quicker? A big WTF to that. I mean, if your front wheel goes, you go - down. And having your front fork fail kinda affects the position of the front wheel...


What I meant was there's this certain point where your going to fall anyway in an accident.. in fact, it happens pretty easily when on a bike. Now if there's an impact, wouldn't you rather it destroy just your fork rather than your fork and frame? I think you read the word "fail" as in a JRA spontaneous fail, which does happen much more often to CF than to anything else, and it is a fault that I forgot to address. But that's not what I meant.


Weight savings.. yeah, it's an insignificant difference, but it's still a difference and this is important to some people.

Time for a new frame.
My opinion-CF is a limited use racing product. You use it, then chuck it. It's time to chuck it.

What I meant was there's this certain point where your going to fall anyway in an accident.. in fact, it happens pretty easily when on a bike. Now if there's an impact, wouldn't you rather it destroy just your fork rather than your fork and frame? I think you read the word "fail" as in a JRA spontaneous fail, which does happen much more often to CF than to anything else, and it is a fault that I forgot to address. But that's not what I meant.

Well, I get what you say but I still have a bit of trouble wrapping my mind around it. I don't mind if my frame has a higher chance to be fubared in such a catastrophic impact, as long as I can trust my fork not to buckle under me, in all riding conditions.

What is a JRA fail?

My LBS friend rode with Fred Landis at a charity event a while back . . . had a chance to chat with him. One comment that impressed my LBS friend was that FL says that he isn't particular or meticulously insistent on how his mechanics set up his bike . . . says seat/bar adjustments don't really make much difference to him and he probably wouldn't notice changes from one ride to the next.

I feel the same way about frames. Five minutes on most any frame, and that's the bike that I'm riding, and I can ride it all day. I'm no pro, but I do a lot of riding.

My old Schwinn was steel, my C'dale was aluminum, my Giant TCR is CF.

The C'dale frame was crumpled under the front wheels of a car. It's just a guess, but, in my mind, neither of the other two bikes would have crumpled like that. CF is extremely strong. If it doesn't break, then, I"m not too worried about it failing spontaneously. I think that characteristic of CF is over blown for practical purposes.

For all the discussions here about CF's propensity to fail spontaneously, how many can relate from actual experience, first hand? I doubt many. I'm not talking about failure in a crash. I'm talking about a frame that fails suddenly with previous damange limited to a scratch or some cracks in the clear coat.

In every day life for every day riders, it just isn't a problem.

We were chasing down some clicks on my TCR at the LBS. During the diagnostics, the mechanic put my BB under a lot of stress. I was surprised (and a bit stressed) as I watched how much flex there was in that frame (one of the criticisms pros voice over my particular TCR model), but nothing cracked.

I ride that bike with confidence. Have taken a couple of 25 mph falls (didn't crash into anything but the road). Everything continues to feel tight and solid.

If the tumble taken by the OP's riding partner didn't involve striking anything stationary except for the road, I would not be too concerned about some scratches or cracks in the finish.

As for fascination with CF, it does allow for some added design capabilities, it is comparatively light, for those of us who like the way it looks, then, it looks cool, it's in, it's comfy to ride (but all bikes seem that way to me), it won't rust, it works. So, without knocking any other tried/true materials, I see no reason to knock CF.

Caruso

If you want to read a bit about CF, Calfee has a nice whitepaper at

http://www.calfeedesign.com/whitepaper1.htm

Now since they make CF bikes I'm sure people will assume this is biased but you can make up your own mind. As waterrockets says if you do crash your CF someone like Calfee can repair it as good as new for a few hundred dollars.

Disclaimer: I ride a CF frame (also have ridden AL & Steel) and I love it and have no fear of failure.

If you want to read a bit about CF, Calfee has a nice whitepaper at

http://www.calfeedesign.com/whitepaper1.htm

Now since they make CF bikes I'm sure people will assume this is biased but you can make up your own mind. As waterrockets says if you do crash your CF someone like Calfee can repair it as good as new for a few hundred dollars.

Disclaimer: I ride a CF frame (also have ridden AL & Steel) and I love it and have no fear of failure.

Yes I read that article and many more about CF as well as most RAAM riders use the same bike from the shop like we do. I'm not worried about it one bit. I've seen so many pictures of bikes after wrecks, that makes you wonder how someone could live through. I rode motorcycles for years as well and I don't care what they are made out of they all look pretty bad.

To get back to the OPs question, yes it can be repaired. I worked on plastic boats for years and some of the work I've seen being done on them after being taken off rocks is amazing. You wouldn't believe how much a mast 100 feet high flexes and they sail them around the world. Yes some do fail, but that is very rare. I think the pounding that race bikes, boats made of CF, or any other material would fail under those conditions. I'm glad those people tested them before we got it, but again, I'm not worried about it and if a rider is worried about it they should pick a different bike.

The owner of the LBS I worked at had a section of CF tubing from one of the brands we carried, and he clamped it in a vise just to see. It didn't actually fail until it was at least 50-60% deflected in shape. He had to really crank it to get it to collapse. It may have at least something to do with the manufacturer. Although I know a majority of CF frames (and AL frames as well) are Asian constrcuted, certain brands use only certain factories and tightly control their product that comes out. The tubing he crushed was Cervelo, and I know they do more extensive testing than many other brands. My own rule of thumb about it was that I never own a frame that either can't be repaired (steel) or doesn't have a lifetime warranty (any good CF make). So there's my ramble about it... sorry.

^That's pretty impressive, you're saying he was able to say, clamp a 2" tube down to 1" before it failed? I find that somewhat reassuring.

My LBS friend rode with Fred Landis at a charity event a while back . . . had a chance to chat with him. One comment that impressed my LBS friend was that FL says that he isn't particular or meticulously insistent on how his mechanics set up his bike . . . says seat/bar adjustments don't really make much difference to him and he probably wouldn't notice changes from one ride to the next.

I feel the same way about frames. Five minutes on most any frame, and that's the bike that I'm riding, and I can ride it all day. I'm no pro, but I do a lot of riding.

My old Schwinn was steel, my C'dale was aluminum, my Giant TCR is CF.

The C'dale frame was crumpled under the front wheels of a car. It's just a guess, but, in my mind, neither of the other two bikes would have crumpled like that. CF is extremely strong. If it doesn't break, then, I"m not too worried about it failing spontaneously. I think that characteristic of CF is over blown for practical purposes.

For all the discussions here about CF's propensity to fail spontaneously, how many can relate from actual experience, first hand? I doubt many. I'm not talking about failure in a crash. I'm talking about a frame that fails suddenly with previous damange limited to a scratch or some cracks in the clear coat.

In every day life for every day riders, it just isn't a problem.

We were chasing down some clicks on my TCR at the LBS. During the diagnostics, the mechanic put my BB under a lot of stress. I was surprised (and a bit stressed) as I watched how much flex there was in that frame (one of the criticisms pros voice over my particular TCR model), but nothing cracked.

I ride that bike with confidence. Have taken a couple of 25 mph falls (didn't crash into anything but the road). Everything continues to feel tight and solid.

If the tumble taken by the OP's riding partner didn't involve striking anything stationary except for the road, I would not be too concerned about some scratches or cracks in the finish.

As for fascination with CF, it does allow for some added design capabilities, it is comparatively light, for those of us who like the way it looks, then, it looks cool, it's in, it's comfy to ride (but all bikes seem that way to me), it won't rust, it works. So, without knocking any other tried/true materials, I see no reason to knock CF.

Caruso

One (not the only) of the reasons you don't see people writing about their CF frames or forks failing for no apparent reason, while they were going some 25-30 mph is, because they're pushing up roses.

If you want to read a bit about CF, Calfee has a nice whitepaper at

http://www.calfeedesign.com/whitepaper1.htm

Now since they make CF bikes I'm sure people will assume this is biased but you can make up your own mind. As waterrockets says if you do crash your CF someone like Calfee can repair it as good as new for a few hundred dollars.

Disclaimer: I ride a CF frame (also have ridden AL & Steel) and I love it and have no fear of failure.

Thanks for the link. That was a good read. I don't feel it was biased at all. They do, of course, espouse the use of carbon fiber, but, it looks to me as though they at least attempted to present a balanced picture of the pro/con of each type of frame construction, even those involving their own bikes.

I once rode a Calfee for a week or so. It was a nice bike.

Caruso

One (not the only) of the reasons you don't see people writing about their CF frames or forks failing for no apparent reason, while they were going some 25-30 mph is, because they're pushing up roses.

As one who has been through the experience of laying a bike down more than once while doing 25 mph or better, I urge you to describe the specifics of failures about which you hypothesize. Speak for those poor rose-pushing souls. What exactly happened that caused the bike to fail, and how did the resulting crash end in the rider's graduation from pedal to rose pushers?

I am well aware of accidents (most involved animals caught in spokes) where riders went over the handle bars at high speeds, but am unaware of numerous cases where frame failures caused those sorts of catastrophes.

I would think that, if a frame failure caused such a catastrophic crash, the evidence would be quite apparent, with or without the daisy-pusher's first hand accounts. Do you, personally, know of one instance where such a crash can be ascribed to CF failure?

Caruso

As one who has been through the experience of laying a bike down more than once while doing 25 mph or better, I urge you to describe the specifics of failures about which you hypothesize. Speak for those poor rose-pushing souls. What exactly happened that caused the bike to fail, and how did the resulting crash end in the rider's graduation from pedal to rose pushers?

I am well aware of accidents (most involved animals caught in spokes) where riders went over the handle bars at high speeds, but am unaware of numerous cases where frame failures caused those sorts of catastrophes.

I would think that, if a frame failure caused such a catastrophic crash, the evidence would be quite apparent, with or without the daisy-pusher's first hand accounts. Do you, personally, know of one instance where such a crash can be ascribed to CF failure?

Caruso

Totally useless answering this question after


Thanks for the link. That was a good read. I don't feel it was biased at all.


Not biased... like Rohloff saying gear hubs are as efficient in transmitting energy as derailers. Too bad the scientist disagree (but hey, I guess it's the scientists to be biased, not a company producing gear hubs -----> this stuff is always biased, and your conscious and forceful decision to ignore this at all costs tells me where your chips are.

I was already a member of BF when a discussion was going on about a famous cycling enthusiast who died from a CF fork failure. But why go through the abuse of using the BF search system, when you'll flippantly dismiss the story with some smart remark? Got no time for that.

But hey, who am I to prevent anyone from spending $2000 on a CF frame and then never know for sure if it's really safe. It looks cool, that's what matters. And oh yeah, a company making CF frames totally said they are safe, so...

You must be kidding. I have seen aluminum frames completely fold up from minor mishaps. I had an AL bike that slightly tipped over in the bike room, resulting in a permanent dent in the top tube. The AL bike that the Look replaced was extremely flexy and would make all sorts of noises when I stood pedaling.

I ride a CF Look, 2 steel bikes, and an AL Bianchi. Steel is nice- no question about it. Still, I believe CF is much the subject of myth and speculation. Before you get too wound up (no pun) about it, consider the new Airbus planes will be CF-- (or maybe DON'T think about it too much ;) ).

BTW- I have a rather hapless friend who has dumped his Trek 5200 more times than I can count--- and it is holding up just fine. The OP had a scuff on the top tube. That had nothing to do with the frame material. Someone else posted an "after" photo after being broad sided by a car. Frame material had nothing to do with it.


Jeez... it seems I'll never regret never having or wanting to have any CF part on my bikes, let alone the frame... There just never seems to be anything appealing about it, and a whole lot of appaling against.


EDIT: seriously, what's the appeal of CF? As someone already said, there are pretty light steel frames, not to speak of Ti. Is it the 300-400g less of weight? Take a dump and there you go - instant CF weight class you and your bike together.
I guess it's the higher price. The stupid "it's expensive, it's GOTTA be good."-mentality. Followed by cognitive dissonance "I invested too much money into this thing, I must defend it at all costs - this thing IS good otherwise I feel stupid".

You must be kidding. I have seen aluminum frames completely fold up from minor mishaps. I had an AL bike that slightly tipped over in the bike room, resulting in a permanent dent in the top tube. The AL bike that the Look replaced was extremely flexy and would make all sorts of noises when I stood pedaling.

I ride a CF Look, 2 steel bikes, and an AL Bianchi. Steel is nice- no question about it. Still, I believe CF is much the subject of myth and speculation. Before you get too wound up (no pun) about it, consider the new Airbus planes will be CF-- (or maybe DON'T think about it too much ;) ).

BTW- I have a rather hapless friend who has dumped his Trek 5200 more times than I can count--- and it is holding up just fine. The OP had a scuff on the top tube. That had nothing to do with the frame material. Someone else posted an "after" photo after being broad sided by a car. Frame material had nothing to do with it.

Airbus? Maybe you're thinking of the Boeing Dreamliner - which is carbon fiber. One of the lead engineers in fact complained that the fuselage wasn't tested enough (with regards to the fact that CF is a novelty in passenger planes) and was promptly fired. Oh well, never mind.

And never mind the fact that I never said CF frames are fragile! Way to put words in my mouth. I said, and I will say that again: CF is nasty because you have no effing clue when it's going to fail. No premonition, unless you're psychic.

Just a brief mention about aeronautical fuselage materials: they are way overengineered - they put several times more of the material for good, good, good, good measure, especially in passenger planes. And then they have very strict mainenance rounds - very regular and thorough. No bicycle, be it steel, aluminum or CF is so overengineered (eccept maybe the old steel bicycles that weighed tens of kg in frame alone).

All in all, I still don't see the appeal. A $2000 frame that I have no clue when it will fail - or a $200 frame that is about as heavy and I actually have some possibility to predict catastrophic failures. Hmmm... really tough to make up my mind. If you are so in love with your CF bike, you definitely must dismiss all I said and categorize me as "full of schitt", for your peace of mind. That's called cognitive dissonance.

In aerospace, there is actually a "coin tap" test for damaged composite structure. Take a quarter or larger coin...

That makes me feel a lot better that they have a "system" in place for CF like X-ray, Sonic or Magnaflux for steel structures and components.

All in all, I still don't see the appeal. A $2000 frame that I have no clue when it will fail - or a $200 frame that is about as heavy and I actually have some possibility to predict catastrophic failures. Hmmm... really tough to make up my mind. If you are so in love with your CF bike, you definitely must dismiss all I said and categorize me as "full of schitt", for your peace of mind. That's called cognitive dissonance.

What's the point of arguing this? You don't trust CF fine don't ride it, but your not going to convince me that CF is dangerous and I'm risking my life by riding it. These CF arguments are just pointless, get on your AL, Steel, Ti or CF bike and go ride already.

Yeah, an AL or Steel frame never gets damaged in a crash:rolleyes:

Yeah I mean steel frames just catastrophically fails with no prior warning.

What's the point of arguing this? You don't trust CF fine don't ride it, but your not going to convince me that CF is dangerous and I'm risking my life by riding it. These CF arguments are just pointless, get on your AL, Steel, Ti or CF bike and go ride already.

+1

The biggest advantage of carbon fiber is not for the rider but for the Bicycle manufacturers. A Steel or Ti bike require a fairly high skilled tradesman to build a good frame and the basic materials are expensive. An Al bike also requires a highly skilled welder and metallurgist to determine the anneal time and temperature to treat the welds but, the materials are very cheap. However, a CF bike requires a skilled designer, a mould, some fiber, a resin and catalyst, and a relatively low skilled inexpensive (but trainable) worker who can layup multiple frames at the same time...gee I wonder if I put in the right amount of catalyst...Hmmmmm???? That is reality. Other than at the highest level of competition where aerodynamic drag of the frame might save 0.5 seconds per mile in a 100 mile race...it don't mean squat for us mere mortals...comfort is our main focus...if you don't like road noise then CF is great, if you like a lot of road noise then an Average Al bike is your ideal, if you like a good ride then steel and/or Ti is great. But, when you are hauling down a descent with your hair on fire then Steel with a conventional geometry is the best...for us mere mortals...One man's humble opinion.

Totally useless answering this question after




Not biased... like Rohloff saying gear hubs are as efficient in transmitting energy as derailers. Too bad the scientist disagree (but hey, I guess it's the scientists to be biased, not a company producing gear hubs -----> this stuff is always biased, and your conscious and forceful decision to ignore this at all costs tells me where your chips are.

I was already a member of BF when a discussion was going on about a famous cycling enthusiast who died from a CF fork failure. But why go through the abuse of using the BF search system, when you'll flippantly dismiss the story with some smart remark? Got no time for that.

But hey, who am I to prevent anyone from spending $2000 on a CF frame and then never know for sure if it's really safe. It looks cool, that's what matters. And oh yeah, a company making CF frames totally said they are safe, so...

Does it make you feel good - do you think you appear smarter by taking a good discussion and making it personal? Why so angry, eh? Read the post previous to the two that you decided to nit-pick. I don't endorse one frame material over the other, and, although the manufacturer in the link provided has made their choice clear, I still think the article is reasonably balanced especially in light of the fact that it comes from a user of CF.

I'd be interested in the account of one CF frame that failed spontaneously, killing the rider. Was that recently, was the bike of recent design, or one of the earlier designs/composites?

I can relate one case of an aluminum wheel failing spontaneously. Broke my arm on that one - but I'm still riding aluminum wheels, not that wheels have anything to do with comparing frame materials. I read good and bad about all frame materials - most of us do. I try to inform myself within reason, then I make a decision and move on it. Most of us are not putting our equipment through such extreme performance requirements that any of this will matter to us.

My guess is that very few of us need worry about frame failure if we purchase decent bikes, no matter what their material content.

You can call that flippant if you want. I call it getting on with life. In the end, as much as I have treasured each of my "machines" they are only bikes. I get on mine and ride 'em.

Caruso

Yeah I mean steel frames just catastrophically fails with no prior warning.

Welds are 100% reliable?

Here comes the CF haters....he he he.....

I jinked this evening and tapped my riding buddies front wheel....down he went at 18-20mph. Aside from his shorts and hip, a fork blade and a portion of his top tube got seriously scuffed. I saw no cracks or penetration. Question: Though an accident, I feel badly.......I'm unfamiliar with cf-- have I shortened the life of his frame or begun a process leading to a future frame failure?

if the crash is your fault, you have got to do the right thing and buy your mate a new CF frameset. I wouldn't ride that crashed frame unless its inspected by a CF repairer. Even then it might not be seen there.

I think ambient temperature may change it's flexibility slightly.
Although there are probably not many that ride a carbon bike in the cold.

Welds are 100% reliable?

Do you really don't get it, or you just act dumb? Nobody said metal frames are more reliable than CF. We're saying that you have no idea when your CF component will fail. With metal parts you have a chance to predict such a failure by examining the part.

Some people won't examine their frame or other metal bicycle part, so if it's about to fail they won't know. Because they didn't check. But they could have.

Some people will see the impending danger and will take action, and avoid a possible disaster stemming from their metal part failure.

CF people just won't notice schit until it's too late.

Do you really don't get it, or you just act dumb? Nobody said metal frames are more reliable than CF. We're saying that you have no idea when your CF component will fail. With metal parts you have a chance to predict such a failure by examining the part.

Some people won't examine their frame or other metal bicycle part, so if it's about to fail they won't know. Because they didn't check. But they could have.

Some people will see the impending danger and will take action, and avoid a possible disaster stemming from their metal part failure.

CF people just won't notice schit until it's too late.

Maybe you should try carrying on a conversation without calling people names. I won't play, try going to P&R they love to play that game

At this point I am just frustrated with bikeforum's useless search system. I know that just a month or two after I joined, there was a discussion about a few poor dudes (one of them was a friend of the BF patron discussing in th thread) who died from CF fork failures. Road cyclists.

I only could find this (at this moment):
http://www.bikeforums.net/showpost.php?p=2022697&postcount=18
http://www.sptimes.com/2005/11/20/Neighborhoodtimes/Bike_fatality_undersc.shtml
http://www.bikeforums.net/showthread.php?t=153065&highlight=trek+broken+fork (I think it's the same accident, but more info)
http://www.bikeforums.net/showpost.php?p=2022707&postcount=19
http://www.bikeforums.net/showpost.php?p=1855577&postcount=168
http://www.bikeforums.net/showpost.php?p=4725272&postcount=37
http://www.bikeforums.net/showpost.php?p=2288259&postcount=21
http://www.bikeforums.net/showpost.php?p=4966386&postcount=2
http://www.bikeforums.net/showthread.php?t=156304

Not all are about fatalities, but most are. So just because YOU didn't die yet, doesn't mean it didn't happen. It just didn't happen to you. I don't expect you to report back to this thread when it does.

Also, if it's really supernecessary and you poopoo what people have reported in the posts I linked to, I can do a more extensive post later on, but I guarantee you, it's atrocious work.

A CF fork on a metal frame might save the rest of the frame in a crash because it fails quicker.
I know that this claim has been controversial, and I hate to argue by anecdote, but I believe that I was saved from potentially serious injury by my composite fork recently. A car turned in front of me and I struck its front wheel with my own at 35km/h. Both fork blades sheared off just below the crown, allowing the bike to ride up the bonnet and deposit me full length into the windscreen (a soft landing if you've never tried it). Had the fork held, then the bike would have stopped very suddenly and might have sent me flying or allowed me to impale myself on some part of it.
More generally, I think that we should have heard about the dreadful rise in cycling injuries associated with composite disintegration if it were a real phenomenon. When I think of the frame material most frequently breaking through overusage among my circle of friends, that would be steel. Again, arguing by anecdote, so I apologise.

The owner of the LBS I worked at had a section of CF tubing from one of the brands we carried, and he clamped it in a vise just to see. It didn't actually fail until it was at least 50-60% deflected in shape. He had to really crank it to get it to collapse.

While that's an interesting demonstration that I would have enjoyed watching (it's always fun to break stuff on purpose), I don't think it does much to address the major complaint people have against CF components: that they can harbor undetectable "micro-defects" that can cause failure without warning after a time. While the CF tube may not have failed outright until it was 60% deformed, how do you know that some of the fibers weren't starting to snap or delaminate at 20-30%?

I don't want to sound anti-CF, as I have carbon forks on both my steel bikes (and they're cheap house brand Performance & Nashbar models to boot), I just think we need to be careful about accepting anecdotal evidence on either side of the debate.

The biggest advantage of carbon fiber is not for the rider but for the Bicycle manufacturers. A Steel or Ti bike require a fairly high skilled tradesman to build a good frame and the basic materials are expensive. An Al bike also requires a highly skilled welder and metallurgist to determine the anneal time and temperature to treat the welds but, the materials are very cheap. However, a CF bike requires a skilled designer, a mould, some fiber, a resin and catalyst, and a relatively low skilled inexpensive (but trainable) worker who can layup multiple frames at the same time...gee I wonder if I put in the right amount of catalyst...Hmmmmm???? That is reality.
I all BS on that one. CF is labour intensive and there's no getting away from that. Also, if you screw up it will fold up under the rider which is not exactly good for the reputation of the company.
In comparison, metal stuff requires much less manual work and can actually be made fully by robots. Merida comes to mind... their frames are robot welded.
I'm not sure if it's welding or CF laying that requires more skill but it doesn't matter all that much. Both will be learned by the employee at which point the amount of work (time) is what really matters.