Is the original color the black and yellow, or has someone already repainted? If the black and yellow are not the original colors, I'd recommend letting a professional paint shop bead-blast off the paint and then do a good job of powder-coating back the original color(s).
If your black and yellow ARE the original colors, the next question is: How much of the original finish is missing to rust, dents, scrapes, etc.? If the damage is relatively minor, buff off the rust with a Dremel Moto-Tool and a steel brush. Then go to your local auto paint store or Hobby-Lobby. Match paint colors by opening a bottle of paint that you think is close. Touch your finger tip to the paint in the lid. Make a small smear of the paint onto an inconspicuous place on your frame. You'll see immediately how good a match you have.
Buy some matching paint, and with a small artist's brush, fill the pits and rust spots on your frame. You may have to buff off the excess paint with some fine sandpaper to get the edges to vanish and the surface to be smooth.
After the paint cures, put on a good coat or two of auto wax. DONE!
The other veterans of this forum may have better advice, but the above has worked fine for me.
Happy restoration and don't forget to take "before and after" photos to post here!
I have a Nishiki Tri-A. Its black and yellow. Whats the best way to restore its original finish? Detailed steps would be greatly appreciated!
Just wondering if this project ever got finished. I have a 1986 Nishik Tri-A (Sold in Australia as a Repco) which was originally Black and Yellow and I would love to see what it would have looked like.