c.1957 BSA 646cc Golden Flash Motorcycle Combination
Registration no. WYL 968
Frame no. FA7 14078
Engine no. CA10 4611
Introduced late in 1949, BSA's A10 650cc twin closely followed the basic pattern established by the 500cc A7 while contriving to be almost entirely different in detail. The existing parallel-twin architecture was retained for the new A10, with 360-degree crankshaft and single camshaft at the rear of the cylinder block, as was the four-speed gearbox bolted directly to the crankcase in a form of semi-unitary construction. The A7 engine was revised along the lines of the new design at the same time while the cycle parts remained virtually unchanged, though the larger twin's 8" front brake was one obvious difference. Fitted at first only to export models, the 4.25-gallon fuel tank became available on the home market after one year, as did the striking metallic beige finish of the 'Golden Flash' version. By the end of the succeeding decade, BSA's rugged 650cc twin had undergone considerable development. On the cycle parts front, the introduction of a swinging-arm frame in 1954 had resulted in the original bolt-up gearbox's replacement by a conventional separate item, while the engine had benefited from numerous improvements including an increase in compression ratio for 1958 and the standardisation of the sports models' high-lift camshaft for 1959. Perennially popular, the model continued in production until 1962 and was a regular choice among sidecarists, who appreciated its pulling power and economy.
The restored example offered here is attached to a Watsonian single-adult 'chair'. A total of just 2 miles (presumably the distance covered since the rebuild's completion) is displayed on the odometer and the machine is presented in commensurately good condition. The BSA 'combo' has been displayed at various events, most recently at The Classic Motorcycle Mechanics Show, Stafford in October 2009. Offered from a private collection, it will require re-commissioning and the usual safety checks before returning to the road. There are no documents with this Lot.