The Williamson Flat Twin was

motorcycle A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising ...

made in

Coventry, UK Coventry ( or ) is a city in the West Midlands, England. It is on the River Sherbourne. Coventry has been a large settlement for centuries, although it was not founded and given its city status until the Middle Ages. The city is governed by ...

by William ('Billy') Williamson, who had been managing director of the Coventry-based Rex company. He teamed up with William Douglas (of

Douglas Motorcycles Douglas may refer to: People * Douglas (given name) * Douglas (surname) Animals *Douglas (parrot), macaw that starred as the parrot ''Rosalinda'' in Pippi Longstocking *Douglas the camel, a camel in the Confederate Army in the American Civil W ...

to develop new prototype motorcycles under the name Williamson-Douglas and employed Billy's brother Harold as a test rider. Douglas had been developing a 964 cc

water-cooled Cooling tower and water discharge of a nuclear power plant Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and no ...

flat twin engine that could be used either for light cars or motorcycles. Billy Williamson fitted this engine into a frame with Douglas-Druid

girder fork A motorcycle fork connects a motorcycle's front wheel and axle to its frame, typically via a yoke, also known as a triple clamp, which consists of an upper yoke joined to a lower yoke via a steering stem, a shaft that runs through the steering ...

s and a Douglas two-speed gearbox and a foot-operated clutch which was launched in 1912 at a cost of £82. In 1913 an air-cooled version was added to the range and in 1914 a

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was added. Production was halted by World War I and in 1919 the only engines available were JAP 980 cc air-cooled side valves, so Williamson redesigned the frame to fit. Unfortunately Billy Williamson suffered a fatal

heart attack A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which ma ...

in 1920 after only twenty motorcycles had been produced.

References

See also