Yes having read up on carbon and looking to get my first carbon framed bike ,one thing has come out that makes me wonder.If just dropping my bike or banging it on the wall on the way out to ride can cause damage then why spend the big $$$? What about potholes?HAS anyone on this forum actually trashed a carbon bike or is this a case of could happen 1 in a 100,000,00.oo?

More careful attention is the main thing. YOu have to be more watchful of stress cracks. If I drop an aluminim bike from resting on a tree I'm not too worried about stress cracks. Carbon is a dif story.

The CF frame is a strong product for cycling use, just not for banging around. If you drop, you have to inspect - more than you would say a steel bike. Especially CF bars - may be worth taking a peek under the tape too after a fall/drop.

(Time for some sarcasm.)

BE VERY CAREFUL!!!!

THIS COULD HAPPEN TO YOU ON A CARBON BIKE.

Just don't drop this one, the replacement cost could be killer.
Withstanding stress forces at mach 2.5, I don't think carbon is all that fragile.

13,000+ miles on our c/f tandem. No problems.
Oh, did break a steel tandem frame . . twice!

there's a couple things wrong with your statement. well, everything actually

the F-117 is composed mainly of aluminum, with titanium in the engine bay and exhaust.

secondly, the F-117 can't even break the sound barrier. it's top speed is 660MPH, or .86 mach. it's actually a very slow aircraft, which is why it's only used for night missions.

back on topic, carbon fiber is strong, but can fail catastrophically when even a very small fracture penetrates the resin.

yea as was said you just have to be careful to not throw it around. and don't do what i did and run into a fire hydrant

This is probably a dumb question but will it ever be feasible to make bike frames out of pure carbon (not carbon fibre), like the kind they use for the Easton EC90 fork? It's supposed to be lighter and stronger and doesn't have the epoxy, or something like that.

https://www.eastonbike.com/PRODUCTS/FORKS/fork_ec90_Aero_'06.html

Hi All-

The honest questions posed above are likely the biggest concerns in anyone's mind who is considering carbon fiber for the first time. Let's face it, for people who are very curious and excited to try a new frame material, it's a leap of faith for many...especially considering the substantial financial investment. I'm envisioning simple day-to-day occurences/stresses that a high-quality rig (whether steel, Ti, CF, or aluminum...) might endure in a typical riding season.

• will the frame be damaged if it's leaned against my car and falls over in the parking lot
• will hitting an unexpected deep pothole damage the frame, assuming it taco'd the wheel
• if my keys scratch it while entering my apartment, can cracks develop along those minor scratches
• is there danger of heat damage to the resin if I leave the bike inside a car during the summertime
• if I have a low-speed crash during a group ride (15 m.p.h. or less) will my frame be trashed
• what are long-term affects of water, humidity, or salty conditions on resin
• if a stone hits it at high speed while it's on a roof rack, what is the likelihood of damage if I'm driving 70 m.p.h.

My guess is that more than a few BikeForumites are interested in giving carbon fiber a whirl, it's just difficult for many to sort the nonsense from the "real deal" genuine facts. That is about as much as I could brainstorm at this point, although there must be many more concerns that fellow posters could add.

~ Blue Jays ~

that's the same as any other carbon fork or frame material, it just doesn't have the decorative 'checkerboard' layer on it.

their CNT technology is just an 'improved' resin that's supposed to be a million times stronger than traditional resin because they use nanotubes.

other ways of strengthening resin is to let it cure slower. though many manufacturers don't do this, because the faster they can make these things, the more they can sell.

easton is marketing this CNT stuff for hockey sticks right now too, and from real world experience, it's not stronger or lighter than any other product using a traditional resin.

If you're not careful, extreme temperatures can destroy your carbon bike. Leave it out in the sun to long, and it will start to melt.

[edit]

this is mostly in reply to BlueJays.

heat does weaken carbon fiber. but not the type of heat which you will see in even the most extreme of daily conditions. leaving it in your car in summer is fine. exposing it to open flame is dangerous.

carbon fiber is incredibly strong, the stresses from everyday riding, and even high impacts should not damage it.

pretty much the only time carbon fiber fails, is if there was damage to begin with. and even very small damage can quickly result in catastrophic failure. small chips and cuts under the clearcoat, into the fiber are very dangerous.

carbon fiber will rarely, if ever fail under stress without previous damage. unless there is a manufacturing defect, which is possible!

yes, your frame could get damaged from a parking lot fall
no, hitting even a very large pothole will probably not damage the frame, unless there was damage to begin with
no, your keys should not cause any damage to be concerned of, unless you really go at your frame and get past the clearcoat into the resin/fiber
no, there is not a risk of heat damage, unless you expose it to very high temperatures like open flame
yes, it's possible your frame could get trashed in a low speed crash.
honestly, i don't know the effects of water, etc. water shouldn't effect the fiber, unless it freezes and expands in the resin/fiber, this happens often with composite hockey sticks, water will freeze in the shafts/blades and weaken the structure
a stone hitting your frame may cause damage, and it may not.

Hi G60-

Both of your posts were very informative and helpful. It almost seems the unique conundrum with this material is that it is simultaneously very strong and very fragile. I'd imagine when someone purchases carbon fiber for the first time, they tip-toe around the bike as if it were made of eggshells. The rational mind says most riders enjoy preserving the paint and appearance of their newest regular frames, so they'll probably behave in the same responsible manner with a CF frameset!

~ Blue Jays ~

Thanks for the feedback, G60. Sad to see it's just a lot of marketing hype.. I was hoping it was some kind of promising "new new" thing.

no need to break the sound barrier when you're trying to be stealth.

I think the biggest concern is that everybody is comfortable with the fact that when metal fails, it usually bends in what may be a minor way, while they're scared that when carbon fiber fails, it breaks catastrophically.

Nobody seems to take in to account just how hard it really is to break carbon fiber.

Hi jimples-

Excellent point. It likely requires the equivalent of riding off a ramp propped on garbage cans like BMX bikes when we were kids.

It probably takes far more of an impact to hurt CF than is commonly realized. The tough part is determining whether minor scratches and dings could turn into damage in the future. It's that whole fear of the unknown. I'm completely absorbed in this topic because I've only had steel bikes and I'm desperately trying to talk myself into something new...perhaps an Aegis or even an Independent Fabrication carbon fiber bike...

~ Blue Jays ~

consider that just about every high end bike has a carbon fork. and the fork blades are the only tubes that are not supported or braced by other tubes...and yet no one gives a second thought to a carbon fork.

I have cracked an aluminum frame and a carbon frame. and yes, I would not put a carbon bike/fork on the roof of my car.

Hi fogrider-

Famed custom framebuilder Tom Kellogg of Spectrum Cycles in Pennsylvania is also completely against putting bikes on roof racks. He prefers to keep them inside a car or truck to prevent damage. I assume you're speaking about flying rocks and debris that could damage the integrity of the carbon fiber?

~ Blue Jays ~

Fogrider-

Please elaborate on why you would not put a C/F bike on a roof rack. Are you concerned about flying road debris hitting the frame or the pressure the rack's locking mechanism puts on the carbon forks?

Just wondering because I'm picking up my new Orca tomorrow and was planning on putting it on my rack. I guess I can fold the back seats down and put it inside the car just to be safe.

Someday I'll post pics of my crashed and cracked CF frame. This was a 20+mph crash, squarely into a car that pulled directly in front of me so there was no chance of braking.

The cf fork shattered as it took most of the impact. The frame has hairline cracks where the internal lug ends but otherwise looks like it wasn't touched. It is still not rideable, but considering the impact it held up pretty well. I didn't hesitate to buy another. It may have held up if it didn't have the internal lug to provide a stress point.

But other than that, I find it pretty indestructible.

What, you mean like a charcoal bike?

yeah...good to see another informed Bf member.

maybe if you live on mercury.....