Vibration isolation mount for scooter powerunit

This paper reports the new design method of vibration isolation mount for the scooter powerunit. In the conventional design, while the engine vibration is efficiently isolated by the link mechanism, the time lag induced by the movement of the link mechanism spoils the riding quality when the rider operates the steering or the throttle. To solve the problem, a new design without the link mechanism was proposed. The optimized combination of the crank balance and the single-axis balancer was used to control the orbit of the powerunit vibration. First, the new equations were introduced to balance the inertial forces and moments at the target position by optimizing the amount and the phase of the crank balance and the balancer. Then, some results from the experimental tests were reported to validate the numerically optimized design. Using this new design method, the riding pleasure can be enhanced without unpleasant mechanical vibration.