Hydro Clutch - Sportster Hydraulic Clutch Assembly KIT for 1971 - 1976 Harley Davidson Ironhead - Maintenance FREE - Self Adjusting - CNC Machined 6061 Billet Aluminum - Custom Chopper Bobber HD This unit replaces the terrible ramp and ball release mechanism on 1971-1976 Harley Davidson Ironheads. No more fade, pour engagement and clutch chatter... Easy Installation - Simply thread the Hydro Clutch into the clutch adjustment hole and plumb to a master cylinder with an 11/16" bore. Billet Aluminum Body - CNC Machined 6061 Aluminum Body. Plunger - 303 Stainless Steel. Completely Maintenance FREE! After the initial installation, the Hydro Clutch is Self-Adjusting. *** THE HYDRO-CLUTCH COMES WITH A LIFETIME FULL REPLACEMENT WARRANTY *** Designed and fabricated in the USA by Machinist Mike