Garelli worked for other motorcycle manufacturers from 1914 to 1918 during which time he won a competition organized by the Royal Italian Army to design a motorcycle with which he used his 350 cc split-single engine.
Garelli traballou para outros fabricantes de motocicletas entre 1914 e 1918, durante este tempo, gañou unha competición organizada polo exército italiano para deseñar una motocicleta que empregou o motor que el deseñou.