BSA C15

1959 BSA C15 motorcycle, 250 cc.

The BSA C15 was a 250 cc single-cylinder ohv motorcycle manufactured by the British company BSA from September 1958 until 1967, and was BSA's first four-stroke unit-construction bike. For most of that period, after the introduction of 'Learner Laws' in 1961, a 250 cc was the largest capacity solo machine that a learner could ride unaccompanied when displaying L-plates in the United Kingdom. A road-going Sports derivative was added in 1961, and off-road versions, for Trials and Scrambles, were also available in the range.

A successor to the C11, the C15 had a completely redesigned frame and 250 cc engine. BSA acquired the Triumph marque in 1951, and the BSA C15 250 cc four stroke was derived from the 200 cc Triumph Tiger Cub, itself coming from the 150cc Terrier. Edward Turner became head of the BSA automotive division and in 1958 BSA introduced the concept of unit construction, where the engine and gearbox were combined in one piece rather than as separate components. The BSA C15 'Star' was the first unit construction model and proved more reliable and economical than C11.(based on Wikipedia article)