Power unit for motorcycle

Object: A power unit for a motorcycle having an engine having a crankshaft arranged in the right and left directions of a body frame and a transmission system including a V belt type automatic transmission provided between the crankshaft and an axel of a rear wheel, which can arrange the V belt type automatic transmission above and can be smaller while preventing the center of gravity of the engine from being high to maintain ride comfort. Means to Solve: A V belt type automatic transmission (48) is spaced from a crankshaft (17) in a plane orthogonal to the axis of the crankshaft (17) and has a drive pulley shaft (60) having an axis in parallel with the crankshaft (17) and a driven pulley shaft(61)having an axis in parallel with the drive pulley shaft (60). The drive pulley shaft (60) and the driven pulley shaft (61) are arranged above a straight line(L)connecting the crankshaft (17) and an axel (16) of a rear wheel (WR) in the side view of a motorcycle.