2wheelchef

I have a carbon frame that's more than few years old and it has a 3' long crack? in the top tube. You can feel it with your finger nail, like a ridge witha sharp edge. It's more easily described like the paper towel tube that was creased and then turned out again and the crease is still visible. The crack seems to go through the clear coat but not all the way through the fiber. It's been visible for a while and has not really changed for apx a year or so. Then after a rainy ride I noticed that if you looked at the frame from the side the wet had high-lighted what lookes the crease running from nearly end to end. This ghost image has no "feel" to it and when the frame dried and after not riding it for a month out of fear it has faded. So the big question is... Is the frame cracked or is it a clear coat defect? Can it be repaired? I've seen adds for kits to "wrap" carbon tubes with resin and carbon fabric that claim to be as good as new. Or is a simple sanding repair of the clear coat possible?

unterhausen

do you have any reason to suspect this frame is cracked other seeing this? I would take it to the shop you bought it from and ask them.

2wheelchef

Bought it used, was told by the LBS here in ATX that I could send it to Calfee Designs (SP?) and they could fix it for $$$$ Was looking around for a cheaper option if one is out there.

graymanandy

2wheel chef

It sounds like the tube was buckled (like the paper towel tube) rather than cracked, but there's no way to tell without having it my hands. If it were a crack that was straight and longitudinal to the tube you could put a layer of dual bias to make the tube hold form and not get worse. If it were buckled the tube would require replacement as there would be general damage to the resin matrix.

I guess a third option would be that you found the end of the cloth on a tube that was built by rolling uni (laid longitudinally) up on a tube. That might explain the sharp edge that disappears. In that case I would add a little resin along the line as filler, sand it and shoot.

I would highly recommend having someone who knows what they're looking at look at it. The guys at the bike shop probably don't qualify in this instance, find a laminator. It doesn't really matter what they make but a surfboard, marine, or auto laminator should be able to tell you what is going on in the laminate. No promises on price to fix it though. You should at least consider opening a dialog with the Calfee guys so you know your options.

Andy

cbchess

there is a guy that does carbon repair for cheaper than Calfee
https://www.kirkleebicycles.com/

and another guy too I read about on MTBR.com but the forums are down right now and I can't find the link