• Motorcycle type 
  • Engine number 
    MS 8415
  • Lot number 
  • Condition 
  • Colour  
  • Location


Property of a deceased's estate
c.1942 BSA 500cc M20
Frame no. WM20 60643
Engine no. MS 8415

BSA launched a new single-cylinder range in 1937. Intended mainly for the sidecar man, the two biggest sidevalve models were the 496cc M20 and 596cc M21, both of which came with rigid frames, girder forks and four-speed, hand-change gearboxes. Ruggedly built and endowed with copious low-speed pulling power, both models were highly successful in their intended role as sidecar tugs and many M20s did sterling service as despatch riders' mounts with Allied forces during WW2. The duo were regularly updated, important developments prior to WW2 including the adoption of a foot-change gearbox and, in the M21's case, a change to a longer-stroke engine and a capacity of 591cc. Production of the M20 ceased in 1955 while the M21 lasted until the end of 1958, though it remained available to special order until 1963. This military-specification M20 is known to have been last taxed for the road in 2005 and will require re-commissioning before further use. There are no documents with this Lot, which is offered without reserve.

Bonhams 1793
101 New Bond Street
United Kingdom
Contact Person Kontaktperson
First name 
Bonhams Collectors’ Car department