The invention provides an exhaust system including a cylinder head having a plurality of exhaust ports. The electromagnetic rotor bar as the magnetic rotating force that connects the slip ring which supplies the magnetic current in an air gap to the rotor bar that connects to the fly wheel, a lever that generates torque. 1\u02dc5 wt % of photo-polymerization initiator, 0. A reflector plate is positioned within the housing at approximately the same level or below the lighting module. The constant voltage circuit has a first voltage holding circuit connected between the gate of an output transistor and an output terminal and a second voltage holding circuit connected between the gate of the output transistor and a ground terminal, and carries out control such that the second voltage holding circuit is enabled when the motor is operated.