We recommend that this be installed by a qualified mechanic with experience doing this type of work. Piston comes with specific instructions for setting the ring gap. Failure to follow these will result in engine failure.The item "04 05 06 RMZ KXF 250 KX250F RMZ250 Ported Cylinder Head Porting Port New OEM" is in sale since Saturday, July 10, 2021. This item is in the category "eBay Motors\Parts & Accessories\ATV, Side-by-Side & UTV Parts & Accessories\Engines & Components". The seller is "bpracingatv" and is located in Upland, California. This item can be shipped worldwide.