TWO-WHEELED MOTOR VEHICLE

A two-wheeled motor vehicle (10) provided with a throttle grip (25) rotated by the driver to change the degree of opening of a throttle valve (31), and also with an exhaust valve (34) which, when a throttle ratio which is a ratio of the angle of operation of the throttle grip to the maximum rotation angle of the throttle grip is between zero and a predetermined value, reduces noise emitted from an engine.