Although there were bicycle-related creations dating back several years before, BSA are considered to have started motorcycle production in 1910, for the 1911 model year. Destined never to have the racing pedigree of other contemporaries, they nevertheless garnered a well-deserved reputation as a solid, dependable means of transport for many enthusiasts. The mainstay of BSA's war effort was the M20 dispatch rider's bike which proved its worth during the conflict. Having been supplied in limited numbers before the outbreak of WWII, war production soared to a total of over 125,000 machines. After the war the ex-WD bikes were sold off in batches and eagerly scooped up by the public, at a time when most new machines were going for export to earn much-needed foreign currency. When sold off, they were sometimes 'civilianised' with a coat of paint by enterprising dealers, or simply left 'as is', still in military trim. Initially used for daily transport, the ex-WD M20s have seen a resurgence of interest in recent times, due to the growth of 'wartime' or 1940s/1950s re-enactment events.
JTO 121D was purchased by the deceased owner in 2005, and appears not to have been used since then. Having been standing since that time, it will now require some degree of re-commissioning or restoration, depending on the buyer's preferences. Documentation accompanying the M20 comprises a current V5C, an old MoT certificate expiring May 1990, and miscellaneous papers.