We offer a Air-Spring conversion system that is based off a K-Tech ORSS system. We currently implement this system into the WP 2017-2027 model AER48 and 85CC sized AER43 Fork. This Spring Conversion system is $590. The conversion system replaces the air cartridge in your left-side fork leg, it can be implemented to include the gold cap preload top, or the stock air fork cap can be implemented to hide the coil spring conversion and all the bike to comete in AMA limited sock classes. No additional cost if you elect to increase or decrease the fork spring rate in the first 5 hours of operation.