So I have a carbon fibre SLK Light Crankset and I managed to scratch up the right crank arm and the end has chipped off. I was wondering whether this is structural damage or cosmetic damage. It has been bugging me for the past few weeks now and I just need some confirmation and reassurance, The OCD really kicked in because it happened in such a stupid way. Really thankful if anyone could help me out!
-
6Does this answer your question? What do I do when I am unsure if a carbon fiber component is safe to use or needs replacing or repairing?– SwiftyCommented Apr 6, 2021 at 19:47
-
5That’s just completely harmless scratches everyone has on their crankarms. As long as you don’t wear through a majority of the carbon fibers in that location you should be fine. Photo of a carbon crank arm cross section: gp1.pinkbike.org/p4pb5189489/p4pb5189489.jpg Apparently on MTBs they have rubber crank boots over the ends of their crank arms.– MichaelCommented Apr 6, 2021 at 20:22
-
1Yes, crank boots will hide the scratches and prevent future ones. You’ve barely gone through the clear coat, and there’s plenty of extra material there anyways, don’t worry.– MaplePandaCommented Apr 6, 2021 at 23:45
1 Answer
A lot of carbon cranks are running around like that. It's almost certainly harmless. If you can dig a fingernail in and feel jagged fibers that might warrant smoothing it down or filling it in and sealing it, but for the most part it can be ignored. Some people use something like heli tape to protect that area. That's reasonable if you're doing the kind of riding that causes impacts here to begin with. If it's bugging you, you can get an opaque protection sticker to cover the damage.
-
A side note: It doesn't seem like this is a gravel bike, but Campagnolo's Ekar gravel group has rubber boots to protect the ends of its carbon crankarms. I believe that's a common thing with MTBs. Commented Apr 6, 2021 at 23:50
-
1Yeah that's another way to go if rock hits are going to be a regular thing. There are generic fit ones of those. Commented Apr 7, 2021 at 0:06