PJ1 'FastBlack', which is a 'pseudo' epoxy, rattle can paint, seems well thought of in motocross circles. I'm STILL in the process of refurbing my R80G/S using the PJ1 (non heat proof) for the chassis finish, on top of an etch primer undercoat . So far I've done the monolever arm. A fairly tough and smooth finish, which touched up very nicely after I accidently scraped it, already!
I think I'm supposed to apply only a very thin coat of the etch primer, something I've found needs great care to achieve.
I may have mentioned this before on the forum, in which case apologies for repeating myself.