BSA’s A10, introduced in late 1949, was a development of the Bert Hopwood-designed 500cc A7 with vertical parallel twin architecture, with 360-degree crankshaft and single camshaft at the rear of the cylinder block. Power went through the same 4-speed gearbox, while all cycle parts remained identical between the two models, but for a larger front brake on the larger of the siblings. By the end of the 1950s, the 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 standardization of the sports models’ high-lift camshaft for 1959. The Golden Flash continued in production until superseded by the new unitary construction twin in 1962.
The 1960 BSA 650cc A10 “Golden Flash” offered here, comes to us from a Northern California collector, and enthusiastic restorer. Purchased in 2015 from an East Coast seller, who purchased the bike to keep in his living room as a rolling work of art. When he took delivery, the fit and finish were indeed beautifully and professionally done, but the bike needed the usual re-commissioning to return it to regular road use. He took it to Raber’s in San Jose, where Bob Raber found the engine to be seized. Bob, Paul Hudson and the Rabers gang were given the greenlight to rebuild the engine completely and add any upgrades to make it as reliable a rider as possible. The fuel tank went to GTL Advantage in Los Angeles to be cleaned and relined, since there was some rust present from lack of use. Several months and approximately $11,000 later, what has been credited by several “in the know” riders as one of the smoothest and cleanest A10’s they have ever seen and ridden.
The rebuild included:
Now, with 2,500 miles on the odometer, reset during the restoration, everything works as it should, including lights (high and low beam), horn and brake light. It starts easily, shifts “like butter” according to our vendor and runs beautifully. It is indeed a motorcycle worthy of both showing and reliable riding.
Engine no. DA10 12201
Frame no. Powder coated over
Location: San Geronimo, California