TRANSMISSION

PROBLEM TO BE SOLVED: To obtain an inexpensive transmission by providing a compact structure for a transmission having a form in which power of an internal combustion engine is transmitted by rotating operation of a shift drum via a first transmission mechanism or a second transmission mechanism. SOLUTION: A gear shift operation mechanism is provided with the one shift drum 4 rotated in a plurality of rotating positions based on gear shift operation and with a shifter 5 guided and moved by a cam groove 41 provided in the shift drum 4 in accordance with the rotation of the shift drum 4. The shifter 5 can be moved to a plurality of selection gear shift stage positions LOW, 2ND, 3RD, 4TH, 5TH selecting a plurality of gear shift stages and a neutral position N which does not select gear shift stages, accompanied by engagement/disengagement operation of the first and second transmission mechanisms. With respect to each of the plurality of rotating positions of the shift drum 4, the cam groove 41 guides the shifter 5 to each of the plurality of selection gear shift stage positions LOW, 2ND, 3RD, 4TH, 5TH and the neutral position N, accompanied by the engagement/disengagement operation of the first and second transmission mechanisms. COPYRIGHT: (C)2010,JPO&INPIT