The Norvin was born in the late 1950s from the hybridization of the Vincent engine and the Norton frame. The idea was to blend one of the most potent powerplant available on the market at that time, with a nimble and sharp Norton Manx racing rolling frame. Soon the racing concept was applied to street bikes, and, as they were becoming more popular, Tom Somerton was thinking about moving to the next step and ambitioned to resume the Vincent production.
The first machine built was featured by Motor Cycle News July 20th, 1960. Somerton intended to keep an image of exclusiveness through a limited production. However facing the challenge of the limited availability of parts and donor bikes, only a few bikes were assembled; some sources say 12 but nobody can confirm this number.
Philippe Guyony © 2014-2016






Vincent-Norton Viscount (1959)
Engine: Vincent Black Shadow 50 degree V-twin
Capacity: 998cc | Bore x stroke: 84 x 90mm | Compression ratio: 8.5:1 | Lubrication: Recirculating oil in frame | Carburettors: twin TT Amal | Ignition: Lucas magneto
Gearbox: Vincent four-speed | Transmission: Chain primary
Frame: Norton Wideline Featherbed | Suspension: Norton Roadholder forks/twin-shock swinging arm | Tires: 90/90×19”/100/90×19” F/R) | Brakes: 8” TLS drum front, 7” SLS drum rear | Weight: 390-lb
Top speed: 125mph+
Price new: £450
Thanks to “The Classic Motorcycle” and photographers Kevin Dean and David Lancaster
Sources:
www.classicmotorcycle.co.uk/articles/2012-11/vincent-norton-viscount#.UbkhtxaEzww
http://vintagemotorcyclesonline.com/features/stories/252-nortonvincent-viscount