Bicycle Mechanics - Chain rubs through carbon, HELP!

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mrkirkman
12-26-07, 10:18 PM
Hello there,

I purchased my first road bike a few months ago. It is a 2006 Giant TCR, compact frame. Anyway, the chain had fallen off the sprocket, and apparently rubbed through the bottom tube. There are a few fibers sticking out, but mainly it has rubbed through the gel coat.

My local bike shop wont touch it and said i might try putting nail coat on it, and I was wondering if I can just cover it with some carbon fiber resin. A good friend of mine builds carbon fiber prosthetics, and can do it, but I wanted to check with the forum first.

Any suggestions? Thanks beforehand.

capwater
12-27-07, 05:47 AM
If you have fibers sticking out you have compromised the structural integrity of the frame. I wouldn't ride it.
Bob Dopolina
12-27-07, 06:14 AM
Pictures?

Deanster04
12-27-07, 06:49 AM
Was this a one time occurrance or did it happen frequently? Find out if your friend can repair the damage. Also where is the damage? What is the "bottom tube" referring to? If it is on the BB shell itself then there is probably no loss of structural integrity but, if it is on the seat tube, chainstay, or down tube then you need a more thorough examination and repair. As Dropolina suggests pics would help.
ang1sgt
12-27-07, 07:53 AM
As someone that has watched, and learned from USAF Structural Repair procedures of F-16 Wings, a few fibers can be fixed and repaired quite well. Your Buddy probably knows more than anyone here about repairs like this and I would probably take his word and advice before anyone on the internet.

The Question should be is, why didn't your shop call their Giant Rep in on the damage, and have him/her make the determination?
Navy_Chief
12-27-07, 08:10 AM
I would trust your friend that works with carbon fiber for a living. He can see the issue in person and make a much better decision on the structural integrity than anybody can online.
mrkirkman
12-27-07, 05:01 PM
It has rubbed through to the metal "guides" on the frame, basically where the bottom bracet connects to chain stay. I took it to the local Giant dealer, and they said basically that yes, its a problem, but not to worry about it, it cant go further since its to the metal inside the frame at the part. I'm going to have some clear coat thrown on top and call it good. Thanks for the help!