Harley-Davidson 1926 Model J 989 cc IOE V-twin engine# 26J6127
1909 marked the appearance of Harley-Davidson’s first v-twin, though it was not until the adoption of mechanically operated inlet valves in 1911 (replacing the ‘atmospheric’ type inherited from the single) that production really took off.
Known by the sobriquet ‘pocket valve’, this ‘F-head’ (inlet-over-exhaust) engine – built in 61ci and 74ci capacities (1,000cc and 1,200cc respectively) – would remain in production for the next 20 years.
The Harley single’s transmission arrangements – direct drive by means of a leather belt – were continued at first on the twin, but the need to make better use of the engine’s power characteristics, particularly for sidecar pulling, prompted the introduction of a two-speed rear hub for 1914, by which time chain drive and a proper clutch had been adopted.
Later that same year a conventional, three-speed, sliding-gear transmission with ‘step starter’ was introduced on the top-of-the-range version of the twin which, with full electrical equipment, was listed from now on as the Model J.
Periodically revised and up-dated, the Model J had gained a front brake, stronger fork and pumped lubrication by the time production ceased in 1929.
This Harley Davidson Model J twin was purchased from George Swain, of Swain’s Photographers Norwich UK in 1956 and rode it for two years before going abroad.
The machine has been kept in storage since the late 1950s and we were amazed that after some fiddling (fresh oil, carburettor cleaning and a new battery) the engine started first kick and runs very smoothly.
An application to retrieve the registration number ‘RP 3004’ (still available) has been made to the British DVLA.
The machine is offered with Harley-Davidson Riders Club of GB dating certificate.