Courtesy of Pat Holmes
This motorcycle was built by Birmingham Small Arms (BSA),
a major British manufacturing firm founding in the 1800's.
BSA did not produce motorcycles until 1905, but by the 1920's it was a recognized industry leader.
By the early 1950's, BSA was the largest manufacturer of motorcycles in the world.
Financial problems forced BSA's merger with the
Norton Villiers Triumph Company in 1971 and the end of the BSA nameplate.
This BSA motorcycle is a 557 cc special, with the motor enlarged from 500 cc.
The case and chain casings are made of cast aluminum rather than the standard pressed tin.
