Glixal ATMT1-020 High Performance GY6 58.5mm 155cc Big Bore Rebuild Kit Cylinder Kit For 152QMI 157QMJ Engine Chinese Scooter Moped ATV 1.Easy installation: You can install this kit directly to your GY6 125cc -150cc engine 2.This Cylinder fits the 76mm Bolt Pattern Engine, It will not work on the 80mm Bolt Pattern 3.Inner Diameter of Cylinder: 58.5mm and Outer Diameter of Piston Pin: 15mm 4.High Quality Durable Piston Rings 5.Include Cylinder,Piston,Piston Ring,Piston Pin,Piston Pin Clip,Valve Oil Seal,Gaskets,Tensioner Gasket,Exhaust Gasket,Intake&Exhaust Studs,Exhaust Nut