Hi Young Pup, good lookin 83 mate I have one of these as well (can see on 2nd page on 450,480,500 roll call), the pipe on the 500 is a GMC pipe and the end silencer has been chromed (chromed aluminium) the pipe is a bit of a work of art from Geoff (was on bike when I purchased it) the coating on the pipe is just the metal Geoff made it out of (like a zinc sheet) and I spray it after each ride with Lanotec so it stops it from rusting.
Shane (Wiltec) Wilson
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