1937 Douglas Aero 600cc Twin Solo Motorcycle

Description

The history of the Douglas motorcycle can be traced back to one WJ Barter, who designed and built a series of largely unsuccessful prototypes before joining forces with the Douglas brothers to build their first 350cc flat twin in 1907.  Developed over time, success in competition followed, particularly at the Isle of Man TT where Douglas took victory in the Junior race in 1912 for the first time.  Following the First World War, during which Douglas produced something like 25,000 motorcycles for the military, the range expanded to include both overhead and side-valve models.  Douglas’ innovative side-valve twin, the S6, was designed by Freddy Dixon and launched alongside a smaller 500cc variant at the 1929 Olympia Show, employing a raft of technological advances including dry sump lubrication, detachable cylinder heads and fully enclosed valve gear, an induction system cast-in with the timing cover and a BTH dynamo driven by gearing from the crankshaft.  Offered in both Touring and Sports versions, the 600 quickly gained a reputation for reliability and smooth running.   Following Douglas’ takeover by the British Aircraft Company in June 1935 the ‘Aero’ insignia was adopted on most models from 1936 onwards, identified by a winged design on the side of the fuel tank.  “A twin is best and Douglas is the best twin” read the slogan but the 600 was becoming a little dated by the late 1930s, retaining old fashioned features like the hand-change gearshift and customers began to drift away.  The Bristol company found itself in severe financial difficulty due to falling sales but the Second World War revived Douglas' fortunes somewhat, with production expanded to include aircraft components as well as industrial engines, generators and light trucks.  It proved an uphill battle and production finally ceased for good in 1957, leaving behind a legacy of superbly engineered motorcycles that enjoy a loyal following today.