1937 Sunbeam Model 9 Series II Motorcycle

Description

The history of Sunbeam can be traced back to one person, John Marston, who by the late 1870s was involved in the manufacture of all manner of household items, eventually branching out into bicycles made under the "Sunbeam" trademark.  As with so many similar concerns, Sunbeam experimented with motorised versions of the bicycles and, from 1912 onwards, released their first motorcycle. Marketed as the "Gentleman's Machine", Sunbeam had been experimenting with overhead valves on their race bikes since the early 1920s and adopted this technology for the production models in 1924.  Catalogued as both the Model 8 (350cc) and Model 9 (500cc), the latter had a bore and stroke of 80 x 98mm and the engine, designed by John Greenwood, had a crankshaft supported by three ball-bearings and primary drive in an alloy case.  Important changes included a kickstart from 1927, along with a rear luggage rack and simplified engine lubrication using a Best & Lloyd pump.  Sunbeam resisted the trend away from the flat tanks until late in 1928, adopting an all-new frame design with a saddle tank for the 1929 model year.  Other changes included enclosed pushrods and valve gear, dry-sump lubrication along with an improved clutch using six springs in place of the single central spring and adjustable damping on the front fork, while a twin port cylinder head was optional on 1930 models.  Lucas Mag-dyno electric lighting and a sidecar were the other options catalogued in 1930, and all were finished in Sunbeam’s weatherproof finish all-black.  These classic British motorcycles are rarely offered for sale in Australia and make wonderful club bikes.