Camshaft Manx camshafts 1951 to 1963 Gearbox Gear identification 1939 to 1945 Miscellaneous ES2 oil filtration Tuning Post-Vintage OHV Single Tuning Data - Models 30M and 40M Previous to 1951 Tuning Data - Models 30M and 40M 1954 - 1955 Tuning Data - Models 30M and 40M 1956 Tuning Data - Models 30M and 40M 1957-8-9 International - Engine Maintenance Supplement Preparation for Racing - Notes from the Norton Works View Version 2 of the NOC Singles Compendium