General Cycling Discussion - Carbon frame damage

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View Full Version : Carbon frame damage


ianh
04-17-06, 06:38 PM
I bought a full carbon frame race bike last week. I was unable to clip out when a car pulled out and fell on my side. I was hardly moving. I later noticed three hairline cracks running length ways, mid way along the top tube. Two on one side each about an inch long and one on the top about two inches long. The cracks appear to be only in the clear coat epoxy finish. Along the top crack there is a small amount of delamination between the clear coat and carbon mat below. Is this reasonable damage for an incident like this? I am not too heavy, only 140 lbs. What do you think I should do? Thanks.


gpelpel
04-17-06, 08:13 PM
I would have your dealer look at it. I do not know the force of the crash so it very difficult to make any judgement. They could only be scratches but better be safe than sorry. Did you hear any cracking noise?
I hope you are fine yourself and got the car's license plate.

TomM
04-17-06, 08:16 PM
Can you post pictures?


ianh
04-17-06, 10:00 PM
Will take some pics and get back to you. Thanks,

alanbikehouston
04-18-06, 06:48 AM
You need to have it checked by your dealer. And, after the dealer checks it, if there is still any question of damage, you need to send it back to the factory for a better check. Multiple layers of primer, paint, and sealer will conceal the actual condition of the outer surface of the tube. Checking the condition of the inside of the tube would require factory expertise.

Falling on your side can deliver a massive impact to both the back and to the rider. A man who had been cycling almost daily for thirty years was killed when he stopped at a stop sign and then fell over and crushed his skull on the concrete. A friend of mine had a similar fall a few years back and crushed her helmet...she got off with a bad headache.

khuon
04-18-06, 06:59 AM
You can do a quick check using some vasoline and a blacklight but this will only reveal a clearcut (no pun intended) crack. Having the manufacturer or professional CF shop check it out is the only way to be truly sure. You might inquire at a local marina or airport FBO as some boat and airplane repair shops have the equipment such as X-ray machines to inspect CF and other materials for microfractures.

Banzai
04-18-06, 10:20 AM
Countdown to the next CF v. any metal alloy debate in 5...4...3...

ianh
04-18-06, 11:05 PM
Update... Haven't managed to get any photos for you yet, but took the bike into my dealer today. They were not sure what to make of it. He could not see any impact point and wants the manufacturer's rep to take a look in the next couple of days. He noted that most CF frames fail at the front or around the crank. No bike for a few days :-( I'm keeping my fingers crossed as the largest crack seems to be following the join of two CF mats. There is only clear laquer on the part of the top tube were the largest crack is and you can see the bi directional CF mat below meets up with another mat edge.

Thanks for all your comments. Has anyone had similar cracking?

Siu Blue Wind
04-18-06, 11:48 PM
I just KNEW there was a reason to be frightened of CF. I freak out because it's on my seatstays.



On my other bike, not
<<<<<<< this one

BlazingPedals
04-19-06, 06:06 AM
Countdown to the next CF v. any metal alloy debate in 5...4...3...

Speaking as someone with a crack in his aluminum frame, I'm not throwing any stones!

MKRG
04-19-06, 07:18 AM
There is no debate. There is only Steel.

GuitarWizard
04-20-06, 04:24 AM
There is no debate. There is only Steel.

While this may have been true back in 1967, things have progressed a bit since then.

Phantoj
04-20-06, 09:09 AM
When a laminate sustains an impact, the damage is likely to be more severe on the side of the surface opposite to the impacted side. So you're more likely to have damage (broken fibers, delamination) on the inside of the tube than the outside.

One particularly germane question: suppose it is damaged - what are you going to do? Will you be offered a free or cheap replacement frame? Or will you just throw away your current frame and have to buy new?

If I couldn't get a free or cheap replacement, I would personally just ride the frame. What's the worst that could happen? I've read of several stories of cracked frames, and the common thread is that the cracked frame generally does not result in injury. If you travel Jobst-approved Alpine passes or are planning a long tour where a frame failure would be very inconvenient, of course, riding with a possibly damaged frame might not be acceptable.

As usual, IMO, your injuries may vary, etc.

Furthermore: while frame failures generally result in no injuries, fork failures generally result in substantial injuries. Check your fork!

Nightshade
04-20-06, 09:42 AM
http://www.bikeforums.net/showthread.php?t=189422

ianh
04-20-06, 08:46 PM
Update !! The manufacturer's rep has taken a look, agreed the crack was weird and agreed to replace the frame under warranty. Great sigh of relief.. My LBS has kindly agreed to lend me another bike for the days prior to getting the new frame. Everyone agreed that any frame should be able to withstand toppling over while forgetting to clip out.

This incident has made me think more about the pros and cons of composite frames. Some really interesting pics on that last post Tightwad. Quality control does seem to be a key issue for composite frame manufacture. The manufacture of composites is far more dependent of the skill of labour, compared to alloy/steel. I have always been an alloy / steel frame cyclist, but was seduced by the offer of carbon comfort for the long rides. My recovery times are not getting any shorter and every little bit of comfort helps.

Unless we all go out and get xray specs, we will never really know what lurks below the glossy paint job of our expensive carbon components. Unless of course they dump us on the road one day..

Blue Order
04-20-06, 08:56 PM
While this may have been true back in 1967, things have progressed a bit since then.Carbon is still suspect after impact, carbon still has a short life span, steel still lasts forever.

Blue Order
04-20-06, 08:57 PM
Unless we all go out and get xray specs, we will never really know what lurks below the glossy paint job of our expensive carbon components...Stress fractures.

You know, those things that don't lurk beneath the glossy paint jobs of outdated steel.

khuon
04-20-06, 09:00 PM
Quality control does seem to be a key issue for composite frame manufacture. The manufacture of composites is far more dependent of the skill of labour, compared to alloy/steel.

If I had a nickel for every time I posted that statement, I'd have a enough money for several new carbon fibre frames. ;)

Bicycle applications of carbon fibre is like lasik eye surgery. It hasn't been around long enough for the majority of old-school cyclists to have much faith in it. It's execution is based on a lot of craftsmanship and skill (contrary to those who think good CF frames are stamped out of a big robotic machine). There are a lot of places where one can make a manufacturing mistake. There's a myriad of construction techniques. The technology is constantly being evolved, advanced and refined.

Ziemas
04-20-06, 10:50 PM
Sounds like very good customer service from the frame maker. What brand of frame is it?

ianh
04-20-06, 11:11 PM
Sounds like very good customer service from the frame maker. What brand of frame is it?

I have been hesitating to name the frame maker. But now that I have the problem resolved it is an Avanti Carbonio 06. Many thanks Mr Avanti for helping me out. Compact frame, it rides well, lovely and smooth.

One of the cheapest full carbon bikes you can get - comes with 105 group set. Who's going to be the first to say "you get what you pay for"??