I found out my chain is damaging my frame near the cassette. How can I repair this?

It was damaged by my cassette in the indoor trainer which I am not using anymore. This is how it looks:

enter image description here

  • Thanks for the responses! More than cosmetic, part of the frame has "worn off" to the point where it gets near the screw as you can see in the picture. You mention I can cover that with nail polish, would plastic bonder work better? It might be fine structurally but I just want to protect it against further damage. Let me know what you think!
    – mtobon
    Commented May 8, 2020 at 16:38
  • 1
    @Michael please post answers as answers. Check this metapost for more. rpg.meta.stackexchange.com/a/6534/63719 (yes RPG but still relevant)
    – Criggie
    Commented May 10, 2020 at 20:10

1 Answer 1


I wouldn't worry about it too much. Most Carbon fiber bike frames utilize some form of alloy dropouts. What you are seeing here is merely cosmetic damage and is unlikely to affect the bike in any way unless you deliberately continue to expose that part to damage.

For repair, I would consider a light coat of epoxy which you could even out and spray paint afterwards to minimize the aesthetic imperfection.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.