239857 Fits Kb264 and Kb272 Series Pistons for 1200 Evolution Sport

These replacement piston ring supports from KB Keith Black Performance are essential for specific piston designs where the ring grooves cross the piston pin hole. While these support rings do not perform a sealing function themselves, they are critical for ensuring the piston rings are properly seated and supported during operation. Most KB pistons come with these from the factory, but they can occasionally be lost or damaged during a teardown or rebuild. This component allows you to restore the structural integrity of your top end without needing to replace the entire piston assembly. They are designed to fit Sportster and XB models equipped with compatible Keith Black performance pistons.