First introduced in 1915, Douglas's 4hp model was intended primarily for sidecar pulling. This sidevalve-engined machine employed over-square bore/stroke dimensions of 74.5x68mm for a capacity of 593cc, and like its smaller siblings used the new three-speed gearbox. This rare 4hp Douglas was purchased by the vendor's grandfather circa 1919/1920 and used extensively with a sidecar attached until circa 1929 (a 1929 tax disc survives). The machine was then dry stored until 1968 when all the black-finished cycle parts were re-enamelled. In 1986 the vendor returned the Douglas to the road with a BSA sidecar chassis attached, and passed his motorcycle driving test on it in 1988. 'DU 1045' was then used extensively until 2002 when the crankshaft broke, and remained off the road for the next 13 years. A new crank was installed in 2015, and the machine is said to run very well on its 18T crankshaft sprocket (16T had been employed for sidecar use). Ongoing maintenance has included re-bushing the front forks; re-covering the original saddle and foot boards; re-plating the handlebars (retaining the original grips); rebuilding the wheels (retaining the original hubs and rims); and fitting aluminium pistons from a Douglas Aero 600. Last ridden in September 2016, this wonderfully original Douglas is offered with a V5C registration document.