Mini-Motor is an Italian brand of 50cc auxiliary engines started in 1946 but also made under license in England at Trojan. Originally the Mini-Motor was made by Vincenti Piatti for driving lathes but he immediately saw the potential to build it on bicycles. The motor sat above the rear wheel and drove it by a roller. Here nicely built up on a Swiss bicycle from also 1951. This MK3 model was made from 1951-1953.