Genuine GX120 Piston Ring Set.

The 120cc engine, being a massed produced general purpose engine has a poor bore compared to engines specifically designed for racing. Therefore ensuring that you have a good seal on the bore of your engine is key to performance gains. We normally try to achieve 2-3% leakage of the rings (0% is impossible to achieve due to ring end gap) which normally requires changing rings at least 3-4 times a season for Sprint Racing and every race for Endurance.

Similarly it may be necessary to hone your bore to ensure a perfect seal by Torque Honing or to de-glaze the bore. New Piston Rings should therefore be fitted after a bore has been honed.

Note we also now stock the New UT1 Piston Rings (part # 13010-Z4F-004). Click here for details. Fitting these piston rings to your engines will make a noticeable difference to bottom end power.