This cylinder block assembly, 4-stroke 125cc air cooled profile, is used for most engine brands commonly found in Chinese ATVs, go karts / dune buggies, dirt bikes and other powersport products. Unit includes the cylinder block 20A8250, gasket set GSK2014, piston set 30A8156 and piston rings 30A8159. Bore size is 54mm. Block size is 124cm3.