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The belt clutching CVT drive has been developed for the scooter application. It utilizes the belt as a clutching mechanism instead of the traditional centrifugal clutch that is commonly employed in conjunction with the driven clutch of the drive train. By eliminating the centrifugal clutch, 48% mass reduction of the driven clutch has been achieved as well as cost saving. By placing the belt clutching directly at the engine crankshaft, fast throttle response and better vehicle acceleration/deceleration have been attained. The belt clutching mechanism demands a better performance belt to withstand the additional clutching induced wear and tear. The newly developed carbon cord belt, G Force™ C12, meets the challenge. The common edge cord pull-out failure mode is eliminated, and the overall wear is improved. An analytical program PTWork has been developed and proven to be instrumental in integrating CVT clutch hardware with the CVT belt.

The dual phase twin synchronous drive has been developed for belt noise reduction. Two identical synchronous belts are arranged parallel side by side with one tooth staggered against other by the half pitch offset. The noise cancellation effect is achieved as one belt tooth engagement coincides with the other belt tooth dis-engagement. A center flange is used as a divider to prevent the belts contacting each other along the axial direction during their entrance and exit of the sprocket. An overall 20 [dBA] noise reduction has been achieved with the dual phase twin belt drive compared to an equal width single belt counterpart. The vibration amplitude of the hub load is also reduced which is directly correlated to the structural borne noise. Comparing to the related dual phase helical tooth belt, the dual phase twin belt is superior in torque carrying capability; and is on par with noise mitigation.