Norton wheel nuts for brazed frames with rear speedo drive (set 3). A new set of Norton Norton wheel nuts for brazed frames with speedo drive on the rear wheel. 7/16 inch x 26tpi, Suit models: 1, Big 4, 16H, 18 1947 to 1955 and rigid twins 1950 to 1953, ES2 1953 to 1955 (NOT the plunger heel models). Original Part Numbers: B2/451; 13268 - wheel sleeve nut rear