1920 JE Smith (JES) 142cc Auxiliary

 PREV  ITEM 93 / 147  NEXT 



1920 JE smith (JES) 142cc Auxiliary

The JES was one of the most popular of the auxiliary engines produced in the 1910s/early 20s, as it had a good reputation for reliability. I sold this one around 2010.



Gloucester, England

JES were motorcycles produced from 1909 to 1924. The name came from the initials of J. E. Smith of J. E. S. Motor Works of Gloucester.

  • 1909 JES was first offered as an auxiliary motor set to fit within a bicycle frame and drive the rear wheel by belt. The engine was a 1hp, 116cc four-stroke with a front-mounted gear-driven Fischer magneto, and the whole machine was a bicycle with braced forks and a fuel tank hung from the top tube.
  • The JES continued in this form for many years and was also built and listed as the City and the Imp.
  • 1920 The engine was enlarged to 142cc and inclined in the frame, but the original simple concept remained.
  • 1921 Added to the list was a 170cc two-stroke miniature motorcycle with two speeds and a vertical engine.
  • 1922 A single-speed version appeared.
  • 1923 The four-stroke was dropped, but the single-speed two-stroke ran on with a three-speed version. To these were soon added a lightweight with four-speed chain-transmission and the choice of 247cc two-stroke or 249cc ohv Blackburne engines – a move to more conventional machines.
  • 1924 The company acquired the Connaught marque of Birmingham, and for that year there were just two lightweight models. One with the 247cc two-stroke, but the other with a 348cc sv engine. Both had three-speed Burman gearboxes and chain-cum-belt drive. The auxiliary motor set was re-introduced. This was a 123cc two-stroke engine, chain drive and in either gents’ or ladies’ style of bicycles frame. It was also available as a conversion kit. The make did not survive beyond the end of that year. The specification sheet reproduced below is for the 1909 JES, which was 116cc.