the 1946 to 1953 long stroke manx norton was initially sohc, the dohc engine becoming available to favoured racers in 1949. the short stroke model (1953 to 1962) had bore and stroke of . it used a dry sump 499 cc single-cylinder motor, with two valves operated by bevel drive, shaft driven twin overhead camshafts. compression ratio was 11:1. it had an amal gp carburettor, and a lucas racing magneto. the 1962 500 cc manx nortons produced at 6,780rpm, weighed , and had a top speed of .