A Brief History of the Marque
Motorcycles built in Milan by Achille Fusi with JAP engines from 175 to 500cc.
Fusi imported FN machines after World War One, and built the first RAS brand machines with JAP engines in 1932, followed by motorcycles powered by Italian-built JAP 250cc and 500cc OHV engines, and sidevalve powerplants from Frera.
Production of their own engines began in 1935 using CF-designed 250cc OHC facecam engines.
In 1936 the marque was renamed Fusi.
Sources: MC Storico Conti, et al.