Suggest install it on single speed bike. (the multi-speed bike) may need modify the small chain or the paddle sprocket. The item "49cc / 66 / 80cc bike gas engine motor parts 2-stroke jackshaft" is in sale since Thursday, May 3, 2018. This item is in the category "Sporting Goods\Outdoor Sports\Scooters\Gas Scooters".The seller is "bgf-motor" and is located in Tomales, California. This item can be shipped to United States, Canada.