V-Twin Mfg. Fork Stem Conversion Kit For Harley The fork neck cup set is used when installing a Big Twin or late Sportster 1 neck fork assembly on early Sportster models. Allows installation of spring forks with a 1 neck stem and includes dust cover, races installed and bearings. Features Includes cups and tapered bearings for 1 fork stems to fit early Sportsters and 45 frames that originally had 7/8 fork stem Remove your existing cups and install these cups into your frame neck and you are ready to install any 1 neck stem fork assembly Spacers can be installed on the underside of the neck for added height