Cylinder Head Assembly - 52mm - 110cc ATVs 612092 This 57mm cylinder kit is

This 57mm cylinder kit is the replacement part for many 4-stroke Chinese  ATVs

and approx

Gaskets & fins on jug are also a help in determining the version you have

Fits Tao Tao DB10 and DB20 dirt bikes

Cylinder Head Assembly - 52mm - 110cc ATVs 612092 This 57mm cylinder kit isChinese ATV Cylinder Head Assembly 52mm 110cc Complete cylinder head assembly with valves and cam for 110cc 4 stroke engines. Fits many makes and models of 52mm engines. Check pictures, specs and measurements for verification of the correct part. Head description: Intake port diameter: 23mm (0. 90 in) Exhaust port diameter: 20mm (0. 78 in) Rocker valve side measurement Timing chain side mounting holes: 49mm (+ 0. 5mm) Rocker valve side measurement