Harley Davidson made Single Cylinder ‘Peashooters’ from 1926 to 1934. Models A, AA, B, and BA were available in side-valve and overhead-valve configurations. The Peashooter was designed for the Australian, New Zealand, South African, Rhodesian, and European lightweight motorcycles market, and it also became a fierce competitor in the AMA 21-cubic inch class races against the dominant Indian and Excelsior models of the time.

The Peashooter earned its name from the popping sounds made by its exhaust pipe. The exhaust sound was a side effect of the motorcycle’s performance tuning. Alongside its unique exhaust sound, the Peashooter was famous for having no brakes, no clutch, no transmission, and a direct drive chain from the crankshaft. These elements moved the Peashooter along at deadly speeds topping out at 100 mph on the racetrack! This was made even more dangerous by the Motordrome style of racetracks that the Peashooter was accustomed to. Motordrome racetracks typically consisted of circular or oval-shaped race courses composed of wooden planks. Courses typically ranged from a half mile to two miles with up to 60 degrees of banking along the way.
The core engine was acquired in the USA. The parts needed to make it a complete engine came from Australia, Canada, and the USA. Other miscellaneous parts were sourced in countries not mentioned above.
Harley Davidson 1931HD singles 45 Twins service manual
Harley Davidson Factory HD 1903-1951 Part Numbers Cross Reference Manual