The Velocette Viper is a British motorcycle made by Velocette between 1955 and 1968. Built using traditional methods and materials, it struggled to compete against more modern machines, so from 1960 the designers added new glass fibre enclosure panels, making the Viper one of the first enclosed production motorcycles.
Development
Introduced in October 1955, the single-cylinder Viper was developed from the 500cc Velocette MSS which also led to the almost identical 500cc Venom.. Designed by Charles Udall, the Viper's 349cc engine had a bi-metal cylinder with a cast iron liner, high compression piston and a light alloycylinder head. Using the same bottom end as its sister bike the 500cc Velocette Venom, the Viper had a lot of chrome plating and was offered in a choice of black or "willow green" paintwork. The Viper was also ahead of its time in being one of the first to have glass fibre enclosure panels from 1962. These panels proved unpopular with the traditional buyers of Velocette singles, as they extended from the front of the engine, level with the top of the crankcase, to the rear pillion footrests.
From 1960 Velocette produced the Viper in a "Clubman" racing version, fitted with TT Amal carburettors, a BTH racing magneto and a close ratio gearbox, with the compression ratioraised to 9.3 to 1. The Clubman dispensed with the unpopular glass fibre enclosure and instead made a feature of its highly polished crankcase and gearbox castings. Supplied with "rearset" controls, lowered handlebars and a steering damper, the Clubman also had a range of optional accessories including a "megaphone" exhaust silencer, a rev counter and light alloy wheel rims.
Viper Scrambler
In December 1958 the Velocette development team built 25 off-road Vipers, which were sent to the United States for evaluation in enduro events. Built to the Viper Clubman standard, the Scrambler had a specially lightened frame and high level enduro styleexhaust pipes.
Viper Special
The Velocette Viper Special was introduced in November 1962 and featured a three gallon tank, pressed steel full width hub and the Velocette MSS rear hub as well as a '100 mph' speedometer in a modified headlamp nacelle.
