There would be five classes: 500 cc, 350 cc, 250 cc, 125 cc and 600 cc sidecar. The historic Isle of Man TT would be one of those races, and this toughest and most dangerous of Grand Prix motorcycle races would be a mainstay on the GP calendar until 1976.
Five classes of motorcycles: 500 cc, 350 cc, 250 cc, 125 cc, and 600 cc sidecars. The Isle of Man TT was one of these races, and this challenging and dangerous Grand Prix motorcycle race was a fixture on the GP calendar until 1976.