SSP-G Stroker Crankshaft for 50cc 4-Stroke 139QMB ScootersSPECIFICATIONS: Overall Length: 247mmThread Size (tapered side): M10x1.25Thread Size (spline side): M12x1.25Bearing Outer Diameter (tapered side): 42mmBearing Outer Diameter (spline side): 47mmNumber of Splines: 26Connecting Rod Inner Diameter: 13mmNumber of Teeth (oil pump drive gear): 16COMPATIBILITY: Amigo – 50cc 4-Stroke ScootersApollo – 50cc 4-Stroke ScootersBaotian – 50cc 4-Stroke ScootersBaron – 50cc 4-Stroke ScootersBintelli – 50cc 4-Stroke ScootersBMS – 50cc 4-Stroke ScootersCoolster – 50cc 4-Stroke ScootersCSC – 50cc 4-Stroke ScootersDiamo – 50cc 4-Stroke ScootersFlyscooter – 50cc 4-Stroke ScootersIce Bear – 50cc 4-Stroke ScootersItalica – 50cc 4-Stroke ScootersJCL – 50cc 4-Stroke ScootersJonway – 50cc 4-Stroke ScootersKandi – 50cc 4-Stroke ScootersKinroad – 50cc 4-Stroke ScootersKMD – 50cc 4-Stroke ScootersKymco – 50cc 4-Stroke ScootersLance – 50cc 4-Stroke ScootersLeike – 50cc 4-Stroke ScootersLinhai – 50cc 4-Stroke