I used Rustoleum on a old KZ650 I had about 10 years ago... It takes a while, but once that stuff is fully cured it is about the hardest paint that you can get
in a spray can. When you get around to painting it really take the time to let it cure before sanding and polishing. Mine was done in the summer and I put it
out in the sun every day for about a month before I finally got around to sanding it. Obviously, you don't need to let it sit that long, but alot of the guys I know
that do custom paint always try and wait as long as they can before final sanding and polish - and even longer before they fill with gas.
I don't think that you'd even need a clear coat on properly cured Rustoleum.... wet sand with 1500 & 2000 with a small rubber block and then polish with some
3M "perfect-it" or a light rubbing compund. You can get those foam polishers that chuck into an electric drill at most auto parts stores for about 10 bucks. Get them
damp and apply the polish/compound. You can finish with your favorite wax.
** Some automotive paint supply places have aerosol cans that have 2-part urethane paint in them. Never used them, but they are a urethane paint with a hardener
which is essentially what provides resistance to gas & oil etc. Probably pricey as well.
You'll be suprised what can be accomplished with a $4 can of Rustoleum & some polishing compound. Costs less than a night at the bar....