Lohmann

Unusual construction of this 18 cc engine was designed by German inventor, Hermann Teegen (1899-1962). The engine was described as a „mixture compressing self-igniting two-cycle motor”. There’s neither carburettor nor ignition system. Instead the engine works on a variable compression ignition system, which is moderated by the twistgrips. It fixes under a bicycle’s pedal crank and operates the rear wheel by roller. Although the engine was not a genuine diesel, it was advertised as a ‘bicycle-diesel engine’. The production started in 1950, and in next 4 years 51 000 of them were built.

Herman Teegen. He designed several similar engines, 3 of which were patented.