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Velocette Thruxton

From CycleChaos
Velocette Thruxton

Introduced in 1964, the Velocette Thruxton represents the ultimate evolution of the company's sporting single. Derived from the Velocette Venom Clubman, the new model came as standard with all the items required to compete in production racing. An Amal GP carburettor and big valve head ensured that the engine could breathe to its maximum advantage. A consequence of the use of the Amal GP was the need for a cut out in the rear right hand side of the fuel tank to clear the instrument. Braking was aided by a twin leading shoe front brake and clip-ons, rear-sets and a humped saddle enabled the rider to adopt a position conducive to exploiting the full potential of the machines. Not visible, but equally important to the performance of the model were a close ratio gearbox, revised cams and strengthened crankcases.

The Thruxton Velocette was the final development of Velocette's pushrod single - a machine that in essence dated back to the mid 1930s, but could top 110mph and still sip fuel at an astonishingly low rate through its massive racing carburetor.

Thruxton is a race track in Hampshire - one of the many wartime airfields that found a new use during the 1950s. Racing centered on the endurance marathon for production machines, the 500-miler. The bikes were substantially catalogue models and the entries were shared between two riders. Over the years many British stars shone in the event, including Dave Croxford and Percy Tait. Machines included the racing Triumph Bonneville, the John Player Norton Commando - and the Velocette.

Velocette singles evolved slowly over the years. Their basic formula was laid down by the 1934 250cc MOV, with the camshaft mounted high up and the pushrods kept as short as possible, while their narrow crankcase, slimline clutch and outboard chain run dated back to the early vintage days. By the late 1950s the machine had evolved into the 350cc Viper and 500cc Venom which went on to set the 24-hour speed record at an average of 100mph plus - an enduring record.

In 1964 the high-cam Velocette reached its ultimate development. The performance of the Clubman's Venom at Thruxton led to the makers offering a performance kit that included a special head with 2in inlet valve and an enormous Amal Grand Prix carburetor, plus oil and petrol tanks cut away.

Although the 1965 500-miler was on an alternative circuit, the Velocette dominated the race, with Dave Nixon and Joe Dunphy. The model soon found favor with sporting riders, for it was a genuine tuned roadster and was well able to cope with everyday use.

Its finest moment came in 1967 the year of the first Isle of Man Production TT. In the 500 class, Neil Kelly took the race at just under 90mph, as well as the fastest lap at over 91mph. Fellow rider Keith Heckles was second.

Only a little more than 1200 Thruxtons were built, although the relative ease of converting a Venom meant that were several more replicas constructed by private owners. In 1969 the ignition system was modified to coil ignition, as the traditional magneto had been phased out by Lucas. This was effectively the swan song, for it bowed to commercial pressure in 1971, still a genuine family firm after 66 years.