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My road bike is aluminum with a carbon rear triangle. The carbon rear slides into the aluminum, and I believe was bonded with some sort of epoxy. The pieces have begun to separate after 2.5 years and the company will not warranty the frame.

Is it possible to repair this by inserting epoxy into the gap and sliding the carbon back in place? What sort of precautions should I take, and epoxy should I use?

If I can pull the carbon out further, should I sand the two surfaces before re-bonding?

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possible duplicate of Fixing Carbon Fiber – joelmdev Sep 26 '13 at 22:27
It's a good question, but it's a duplicate. Don't do it yourself. Call Calfee. – joelmdev Sep 26 '13 at 22:28
If I attempted this (which I might because I'm kind of a DIY guy), I'd reenforce the joint with a carbon or fiberglass wrap, vs just relying on epoxy. – Daniel R Hicks Sep 26 '13 at 22:40
Catastrophic frame failure due to poorly informed DIY? No thanks. – Carey Gregory Sep 27 '13 at 2:09
The linked possible duplicate is about fixing a hole in carbon. This question is about bonding carbon to aluminum. They appear to me to be two different questions. – jimirings Sep 28 '13 at 17:29
up vote 5 down vote accepted

I am posting this as an answer but it is more of a long comment. The information I have is from the place I trust to do carbon repairs. According to Hot Tubes aluminum and the carbon resin react. The aluminum must be sealed to get a good bond. The materials are not your hardware grade epoxy. If we were talking about a fishing rod or something that would not cause serious injury in the event of failure I would say go for and try to fix it yourself. My thought is there is enough information and the resulting horror stories of catastrophic frame/component failure to warrant at least getting a professional opinion.

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Yeah, no kidding. – Carey Gregory Sep 27 '13 at 2:08
Seconded. There's a good chance that some fancy proprietary epoxy is used. Good luck acquiring that at a hardware store. There's also the fact that the gluing itself may require special tools, techniques, and conditions. Seconding staying far away from a DIY solution. – moshbear Sep 27 '13 at 12:17
I took this advice and found a place in town ( to do the repair. It was worth it (for peace of mind) to not fix it myself, the repair was pretty cheap and comes with a 5-yr warranty. – mrsoltys Oct 8 '13 at 1:31
@mrsoltys Good work - a 5 year warranty is longer than the frame maker's warranty! So, after ~2 years how is it holding up ? – Criggie Nov 25 '15 at 8:40

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