Diameter:26mm/1.02"(as shown in the picture). Kick Start Idle Shaft Gear 7 Spline for gy6 50cc 139QMB Starter Chinese Scooter. 7 Tooth replacement for 4 stroke GY6 49cc 50cc 80cc 100cc Chinese Made engine. Four Stroke Scooters with the QMB139 Engine,Replacement for Scooter,ATV Motors taotao baja roketa.
