Roller bearings 1/4 x 1/4 inch - each Suit Norton clutch bearing cage, later Burman gearbox, big end on early machines BURMAN B52 Bur-18-2-1 Norton all models A2/383; 000075;06-7618 AJS Matchless from 1951 18-2-1 post 1956 000075;06-7618