High Quality Content by WIKIPEDIA articles! The 1965 Grand Prix motorcycle racing season was the 17th F.I.M. Road Racing World Championship Grand Prix season. The season consisted of thirteen Grand Prix races in six classes: 500cc, 350cc, 250cc, 125cc, 50cc and Sidecars 500cc. It began on March 21, with United States Grand Prix and ended with Japanese Grand Prix on October 24.