 After 1959 the Model 50 gained the Featherbed frame, Lucas RM15 crank-mounted alternator (upgraded from magneto/dynamo used on 1957-58) coil ignition and improved lighting.In common with other large Nortons, the frame was updated to the 'slimline' version with revised styling in 1961.When road testing a used example provided by a London dealer in 1964, UK monthly magazine "Motorcycle Mechanics" reported top speed with cruising.