I took mine off, wet and dry sanded them down, spray painted, primer, ford panther black and they look fine.
Early fzs600 had bare alloy forks so corrode, can't remember what year they changed but about the time of the foxeye I think then they painted them silver. the problem with painted ones is you get stone chips which then sets off/exposes the alloy below and then it corrodes and the paint bubbles so need painted every couple to few years in my experience..
Chris