Parts such as the Shift Cam Fork: Shift Cam Assy, Pin,dowel (137), Stopper Lever Assy, Spring, Tension (256-18143-02) are included in the Xs650s Heritage Special 1983 (d) Usa Shift Cam Fork parts fiche.
The component with the lowest price in the SHIFT CAM FORK schematic is the Bolt Hexagon 341185940000.
With four applications this Pin,dowel (137) is the most specified part.