HO Twin

Horizontally Opposed Twin

Examples include BMW, Zundapp and Douglas HO Twins have conrods running on a common crank, with one on the exhaust stroke and the other on inlet.

Shaft Drive

Examples include BMW, Zundapp and Velocette LE Cardan drive eliminates chain and associated mess and maintenance. Often referred to as a "diff", the final drive unit consists of bevel crown and pinion gears.

BMW Motorcycles

Today in Motorcycle History

BMW R-12 1938

BMW R-12 750cc 1935-1942

In 1935 BMW introduced two models with telescopic forks, the sidevalve R-12 and the OHV R-17, the first motorcycles to incorporate hydraulic shock absorbers in the front suspension.[1]

Production years: 1935-1942, 36,000 built
Power: 18 CV at 3.400 rpm
Capacity: 745cc
Engine: Boxer 4-stroke, sidevalve
Transmission: Cardan
Maximum speed: 110 Km/h
Weight: 185 Kg approx.

N.B. 1. It has been suggested that Nimbus introduced damped telescopic forks earlier than BMW.