Greg
I recently built a 1991 Bully Piston Race here is a parts run down. I did a lot of research into 1990/1 era race bikes so this bike is very era correct.
Parts list:
Frame: Bully Piston Race
Forks: Bully Race
Headset: 1" Chrome
Bars: Bully Race
Stem: Bully Block
Grips: Odyssey
Brake Lever: Dia-Compe Tech-77
Brake Caliper: Odyssey Pitbull
Cranks: Cook Bros
Chainring: Pro Neck
Pedals: Sunn
Seat Post: Bully Beater
Seat: Bully
Hubs: Sun
Rims: Sun
Tyres: Comp III (20x1.75)