Flying Horse 2-Stroke Motorized Bicycle Engine Clutch Spring &ndash; Gas Bike Clutch Spring Replacement This 2-Stroke Clutch Spring is to help disengage and engage your motor's clutch plate, whether you run a 66/80cc or a 48cc bike engine Installation is a breeze: simply take your clutch plate off, place the clutch spring in the center of your bevel wheel, re-install the clutch plate, and your engine is ready to rock Made for engines older than 2012, or for newer engines that may need just a little help engaging and disengaging their motors Note: You may need to readjust your clutch after installing this spring, as your clutch plate may come in contact with the case with too much pop