English: Georges Bouton during a test drive with the 1894 De Dion-Bouton Tricycle prototype. This vehicle got a tiny single cylinder engine delivering 0.5 hp @ 1500 rpm from 138 cc displacement. B x s was 50 x 70 mm.this air cooled unit was the first engine to use light alloy to reduce weight. Picture as published in "The AutoCar", 1906. At this time, these tricycles were considered automobiles, as the term motorcycle not yet existed.