JAP speedway engine

As seen in many a bike on this very blog, the mighty 498cc two-valve OHV motor developed by JA Prestwich of Tottenham, North London, specifically with speedway racing in mind. It was long-serving engineer Stan Greening who created the motor, working closely with top Stamford Bridge (London) speedway riders, Bill Bragg and Wal Phillips, during 1929/30. The motor, influenced in its finer details by the then leading four-valve Rudge, went on to dominate the sport right into the 1960s.

This gorgeous drawing is probably by John Ferguson, who did a stack of great work for the British weekly The Motor Cycle (aka, The Blue 'Un). The advert below is from 1950. MP