Detail showing the motorcycle's suspension. Made by BSA (Birmingham Small Arms) Cycles Ltd at their Small Heath Works in Birmingham from 1948 to 1958, this machine designed by Erling Poppe has a self-contained engine and gearbox unit arranged for shaft drive. It is an example of the advanced design, on motor-car lines, which was adopted by a few manufacturers after 1945 as a progresive alternative to the long established single-cylinder, chain-driven type of machine. The large-section tyres, used in conjunction with the telescopic front forks and sprung rear frame, make the S7 one of the most comfortable motorcycles ever designed fro long-distance touring.
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