Durability of carbon frames
#29
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#30
Another serious answer. I had a nasty 30 mph crash on my Cervelo R3. It was fine and I rode it for another four years. Then the BB shell came unbonded and Cervelo replaced it under warranty (actually I paid the difference and got an R3SL).
A teammate brought his new used R3 on a group ride and there was a slow speed pileup. Normally not a problem but a "large sprinter dude" landed the wrong way on his frame and cracked it.
He got it repaired by Calfee and rides it now.
Cabon frame repair is often cheaper than Ti or steel frame repair.
A teammate brought his new used R3 on a group ride and there was a slow speed pileup. Normally not a problem but a "large sprinter dude" landed the wrong way on his frame and cracked it.
He got it repaired by Calfee and rides it now.
Cabon frame repair is often cheaper than Ti or steel frame repair.
#31
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From: North of Mayo Clinic Minnesota
Bikes: Trek 820 Madone 6.2. Trek 2.1
When I purchased my last bike I was concerned about carbon especially with my weight and some of the bumps on the roads around here. I was told not to worry try to avoid bumps and curbs blah blah blah. But going to the LBS the other night and seeing Mountain bikes made out of carbon I guess I forgot about my own worries.
Gary Fisher
Gary Fisher
#34
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Taken from another thread
Same thing can happen to steel when you get down to those .016" tube thicknesses (less than 4 times the thickness of a beer can).
I had a steel frame on a not so light bianchi that folded the down tube hitting a curb at 10mph.
Exposing any frame material to stresses they are not designed to handle can make them fail.
The thing I dislike the most about aluminum is that the extremely thin walled tubes, necessary to make the frame competively light, make the frame susceptible to denting.
My wife's CAAD 8, suffered a fatal dent in the top tube from the bike falling over in the garage.
My wife's CAAD 8, suffered a fatal dent in the top tube from the bike falling over in the garage.
I had a steel frame on a not so light bianchi that folded the down tube hitting a curb at 10mph.
Exposing any frame material to stresses they are not designed to handle can make them fail.
#35
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My old steel frame had a dent in the down tube for 8 years after a kid on a cycle path rode in to me. Eventually it was the chain stay that snapped all on its own due, I guess, to fatigue. The carbon fork was on the bike for 11 years, had who knows how many miles on it and outlasted the whole bike.
And that was 1990s carbon...
And that was 1990s carbon...
#39
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The reality is that although all frames may break, some break easier than others. CF breaks considerably easier than others.
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#40
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#41
"Chooch"
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From: Prairieville, Louisiana
Bikes: Late 1990s Ciocc Titan
I'm a really big fan of vintage lightweight lugged steel, but if carbon fiber wasn't a suitable frame material then it wouldn't be exclusively ridden by pro riders in all major races.
#42
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Firstly lets be clear Stan, you can believe whatever you want. And you can buy whatever you want. But I will voice the opposing opinion where it's warranted, without fear of intimidation from those struggling with cognitive dissonance issues.
You bought it, you live with it. But to the new consumers my advice is . . . buyer beware, we're talking plastic versus metal.
You bought it, you live with it. But to the new consumers my advice is . . . buyer beware, we're talking plastic versus metal.
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#45
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Stan, how elementary can a discussion get? Tell you what, when you can substantiate your apparent position that cf breaks at the same rate as metal, then I'll bother to substantiate mine. So let's just leave the statement in its complete and inarguable form, that is, some materials break more easily than others. End of argument. Adios.
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#46
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Billy,
Never mind. I ask for proof. I didn't argue against your statement, and you said "So let's just leave the statement in its complete and inarguable form, that is, some materials break more easily than others. End of argument. Adios. " Again, all I aksed is something that supports your statement. That's pretty clear. Apparently you can't
Never mind. I ask for proof. I didn't argue against your statement, and you said "So let's just leave the statement in its complete and inarguable form, that is, some materials break more easily than others. End of argument. Adios. " Again, all I aksed is something that supports your statement. That's pretty clear. Apparently you can't
Last edited by StanSeven; 02-24-11 at 10:08 PM.
#50
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I don't have time to really research into this, but here is a quick table: https://www.performance-composites.co...operties_2.asp
You might be able to find a better table that lists properties like tensile strength, compressive strength, Young's modulus, etc. This has all been researched and is part of Materials Science. But quickly, that table shows that carbon fiber is weaker than metals, especially when it comes to compressive strength. For some applications, carbon can be better at the same weight as the metal, but overall, carbon is more brittle than metals, which are ductile. This is pretty much known. Sure, some producers try to overcome this, but there is no standardization of carbon fiber production, and this is why engineers stay away from carbon, at least for now.
Also remember that steel becomes stronger the more carbon is added, but at the same time this additional carbon makes steel brittle.
There is some great hope in the future of carbon nanotubes, but that's still the future.
You might be able to find a better table that lists properties like tensile strength, compressive strength, Young's modulus, etc. This has all been researched and is part of Materials Science. But quickly, that table shows that carbon fiber is weaker than metals, especially when it comes to compressive strength. For some applications, carbon can be better at the same weight as the metal, but overall, carbon is more brittle than metals, which are ductile. This is pretty much known. Sure, some producers try to overcome this, but there is no standardization of carbon fiber production, and this is why engineers stay away from carbon, at least for now.
Also remember that steel becomes stronger the more carbon is added, but at the same time this additional carbon makes steel brittle.
There is some great hope in the future of carbon nanotubes, but that's still the future.







