Velocette Venom

Introduced in November 1955 and launched at the same time as the 349 cc Velocette Viper, the single-cylinder Venom was developed from the Velocette MSS and needed to compete against a new range of British twin-cylinder motorcycles. Conceived by Velocette’s Eugene Goodman and designed by Charles Udall, the Venom's 499 cc engine had a bi-metal cylinder with a cast-iron liner, high compression piston and a light alloy cylinder head. The design of the engine's high cam with short push-rods was simpler to produce than an OHC engine. The Venom had high quality chrome plating and was finished in black paintwork with gold pinstriping. The Venom was also ahead of its time in being one of the first to have glass fibre–enclosure panels from 1960. 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.

An unusual feature of the Venom design is that the clutch was between the gearbox and gearbox sprocket rather than the conventional configuration in the primary chain case on the far left, with the gearbox sprocket between the clutch and the gearbox. This made the clutch less accessible but allowed for easy gearing changes and a range of sprockets with different numbers of teeth could be fitted by removing the sprocket cover. The gearbox was also a novel Velocette design with a constant mesh close ratio unit that could be maintained relatively easily while still in place.

Simply designed with single top and down tubes, the Venom's heavy brazed-lug frame (which had clear origins in bicycle manufacture) was well proven for its handling capability. At the rear was an unusual swinging arm design with two arms in place of the traditional two prong fork. Although this was effective, it was complicated to set up the alignment. The rear shock absorbers were originally made by Woodhead Monroe, then replaced by Armstrong units and eventually Girling shocks. These could easily be adjusted to suit the rider's preference by moving them in special curved slots. The front telescopic forks (designed by Velocette and manufactured in-house) had hydraulic damping and an offset wheel spindle.

The Velocette Venom used Miller electrics up to 1962, with a belt-driven dynamo. After 1962 this was upgraded to a Lucas system. The speedometer, ammeter and light switch on the original Venoms were fitted into a steel headlamp nacelle; the optional rev counter had to go on a bracket. Later models with Thruxton forks had conventional headlamp brackets and separate instruments.

Eventually becoming the best selling 'flagship' of the Velocette motorcycle range, the Venom is now highly sought after as a definitive example of a British sports four-stroke single.