CP Pistons brand 2004 - 2008 Honda CRF250R FULL RACE Project X Platinum kit. For use in high performance and racing engines; for use with a standard size bore of 78mm; and stock stroke of 52.2mm; 14.5-1 compression ratio; Piston uses a pin that is 1mm smaller than stock and works with Carrillo connecting rod that is 2mm longer than stock. kit includes light weight piston; light weight piston pin; piston rings, pin lock rings, Carrillo racing connecting rod, and Cometic gasket kit. In addition to the standard features, this FULL RACE piston also includes coated piston skirts, dual pin oiling, broached oilers and lateral gas ports to provide improved ring seal and greater power. Project X series piston.