Featherbed frame

The featherbed frame was a motorcycle frame developed by the British Norton motorcycle company to improve the performance of their racing motorcycles around the twisting and demanding Isle of Man TT course in 1950. It was considered revolutionary at the time, and the best handling frame that a racer could have. Later adopted for Norton production motorcycles, it was also widely used by builders of custom such as the Triton, becoming legendary and remaining influential to this day.

The Featherbed inspired other frame builders who based their own products on similar principles, including the heavyweight Münch Mammoth and a lightweight version for a 250 cc BSA C15 engine.

The Featherbed was replaced by the Norton Isolastic frame in 1967 for the then newly-developed Norton Commando which used a rubber-mounted engine and gearbox, although Norton continued to offer the Mercury with a Featherbed frame until production ceased by 1970. Replicas of the frame continue to be produced by specialist companies.

In 1949 brothers Rex and Cromie McCandless offered Norton a new frame to support their successful 500cc race single. Rex McCandless was a self-taught Belfast motorcycle engineer and raced competitively with his brother on a Triumph Tiger 100. He had made several improvements to the Triumph, notably an innovative new frame with a swinging arm fitted with vertical hydraulic shock absorbers from a Citroen car.BSA bought several of his converted motorcycles but Norton saw the real opportunity and contracted him to work exclusively for them from 1949. The Norton Motorcycle Company were concerned at the reliability of their plunger (or "Garden Gate") frame, as several had broken through the stress of racing. Norton engineer Joe Craig solved the problems by making the frames heavier but handling suffered as a consequence.

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