Charles Redrup had been interested in both rotary and radial engines as early as 1904 and in 1912 he built a combination engine that was mounted in a motorcycle so that both sections drove the rear wheel by shaft.
After the end of World War I, he produced a design for a radial three-cylinder engine, rated at 2.75hp. His main interest was in engines, but in order to prove it successful, he commissioned a few complete machines. One such machine was entered and ridden by himself in the 1920 A-C. U. (Auto-Cycle Union) Six days Trial.
During 1921, the rights to the production of the Redrup engine were acquired by the British Radial Engine Co, who made motorcycles of that name.
- Note: Some Beaumont machines were fitted with this engine.
Sources of Information
- The British Motorcycle Directory - Over 1,100 Marques from 1888 - by Roy Bacon and Ken Hallworth. Pub: The Crowood Press 2004 ISBN 1 86126 674 X
-  The Redrup Radial Engine