GY6 Moped 50cc Piston Kit Ring 39mm 139qmb TANK ROKETA JALON STRADA TaoTao Peace Complete piston set with ring, spring, pin and head gasket. Fits GY6 50cc ATVs, mopeds, scooters, and Go Karts Piston Diameter: 39mm Piston Pin Diameter: 13mm Height: 32mm