This tapered roller bearing conversion kit replaces the loose 1/4" ball bearings, cups and cones that are in a stock Triumph motorcycle neck. This kit fits all 650 Triumphs from 1956 - 1970. This kit will fit Triumph 500 models 1967 and up. Simply use a drift and hammer to drive out the old bearing races from your frame's neck, and tap these new races into place. The bearing with the dust shield goes on top and the other on bottom. That is it, simple!