A power transmitting apparatus comprising a clutch housing, an input member connected to an engine and mounted thereon, driving-side clutch discs, a clutch member connected to an output member, driven-side clutch discs arranged between the driving-side clutch discs, a pressure member for press-contacting the driving-side clutch discs and the driven-side clutch discs together and for releasing the press-contacting force on them, and a starter, such as a kick-starter, able to apply a rotational force to the output member to start the engine, the power transmitting apparatus adapted to transmit or cut off driving power of the engine inputted to the input member to or from the output member. The power transmitting apparatus can comprise a press-contact assisting cam of an inverse-driving side for increasing the press-contacting force on the driving-side clutch discs and the driven-side clutch discs when rotational force is applied to the output member by the kick starter.