Starter Motor for GY6 125cc 150cc 152/157QMI 152/157QMJ Scooter Moped ATV Quad Go Kart Yerf Dog Spiderbox GX150 Hammerhead Twister Brand new starter motor for 125cc and 150cc Chinese GY6 4-stroke engines QMJ152/157 QMI152/157 Fits Hammerhead Twister 150 series; Yerf Dog GX150 SpiderBox 150cc; 150cc Eton Seaseng Mopeds ATVs Go Karts. 9 Tooth Sprocket. Center hole to center hole: 79mm (3.11")