My scooter releases the engine below 15 MPH so I slow to 15 MPH, cut engine, ensure engine shuts off, turn engine run switch back to run position so the scoot registers the miles coasted, prepare to re-start the scoot when balance becomes difficult. Go here
http://auto.howstuffworks.com/cvt2.htmto learn how CVT's work. I can explain it but this link is pretty good. The belt disengaging the engine happens below 15 MPH due to the centrifugal clutch slowing down and the clutch shoes releasing the drum.
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