emu
British Motorcycles

Williamson Motorcycles

Williamson of Earlsdon, Coventry.

  • Williamson were motorcycles produced from 1912 to 1920 by William "Billy" Williamson after he left the board of Rex, aided by his brother Harry.
  • 1912 The first machine made its debut and offered power with silence, and no vibration, courtesy of its 8hp flat-twin water-cooled engine, made for them by Douglas of Bristol with whom they had an arrangement. As it was part of their stationary engine range, it had a starting handle, like that of a car. It was a typical Douglas HO twin engine with side valves, gear-driven magneto and was positioned low in a long frame to drive a two-speed Douglas gearbox with all-chain drive.
    HO Twin

    Horizontally Opposed Twin

    Examples include BMW, Zundapp and Douglas HO Twins have conrods running on a common crank, with one on the exhaust stroke and the other on inlet.
  • 1913 An air-cooled version of the horizontally opposed longitudinal twin was added, but it did not sell as well as the quieter machine and had a tendency to over-heat. It did, however, continue to be offered as an option. Most models sold were water-cooled and used for sidecars.
  • 1916 Production continued until that year, and then stopped until after the War.
  • 1919 Late in the year they returned with the air-cooled flat-twin and a new model with the 771cc sv JAP V-twin engine and three-speed Sturmey-Archer gearbox with all chain drive.
  • 1920 Only the V-twin remained, this being sold with the sidecar as a complete combination. It was their final year of production.
  • The company also built automobiles from 1913.


Sources Grace's Guide



If you have further information or a query related to this page, please contact us

Melbourne Motorcycle Workshop
Melbourne Motorcycle Workshop
Dyno Tuning, Performance Enhancements, Sports Bikes and Offroad. Rebuilds, Race Preparation and Classic Restorations.