I have a 2014 street glide and the horn cover always get carbon on it I had it at the dealer a couple of time but they can't figure it out they said compression check good, have anyone seen this if so what did you find.
Never heard of it. Where on the cover are you getting carbon build-up? The only possible way I could think of would be a leaky head on the left side, but you should be able to hear that. Interesting.
