Arrangement of electrical devices on a motorcycle

The present invention concerns an engine 10 having a crankcase (15) extending in the longitudinal direction of a vehicle body, a cylinder (16) located before the crankcase and extending almost upward, a cylinder head (17) located above the cylinder, and an AC generator (30) built in the crankcase (15) characterized in that a regulator (24) for regulating output voltage of the AC generator (30) is held behind the cylinder (16) and on the top surface of the crankcase (15) through an electrical device mounting stay (26). Advantageously, the electrical device mounting stay (26) is fitted through heat-insulating rubber and a first capacitor (25a) and a second capacitor (25b) which substitute for a battery are also fitted through heat-insulating rubber to the electrical device mounting stay (26).