I'll say up front, I'm very anal with my bike. I have a FMF pipe with a half dozen rides on it. I clean the bike up imediatelly after use, dry the pipe, then WD-40 it. It still seems to develope a stained look at the first eight inches of the headpipe, and just after the coupler on the silencer. Polishing seems to have no effect. It is the nickle plated woods pipe. Do you all have any tricks, or do I just have to live with it?