Crank Shaft for GY6 150cc ATV, Go Kart, Moped & Scooter The item fits for GY6 150cc Engine. Inside diameter of crankshaft arm:15mm Bearing model:63/22/P5/S Length:280mm Thin level sprocket(timing driving sprocket):17 teeth Wide level sprocket:17 teeth/17 teeth Thin level spline:19 teeth