There are 5 main categories in Historic Road Racing:
Pre-war extends to the early days of motorcycling, and machines in this group are limited.
Classic [1945- 1963] racing involves solo and sidecar machines, such as Norton, Triumph, AJS, Ducati, Arial, BSA, Vincent, Benelli are among a long list of brands participating.
Post Classic [1964 – 1972] includes Honda, Jawa, Ossa, Kawasaki, Suzuki and the Forgotten Era [1973 – 82] covers all the Japanese manufacturers, European Ducatti, Laverda etc and includes the early Superbikes.
New Era covers machines 1983 – 1990 and includes 750 and 1000cc Superbikes, 250 Production 2-Strokes and 125,250 and 500cc GP bikes.”
Sidecars from all these periods number up to 40 machines for a noise a and rubber filled starting grid.