Parts such as the Crankcase Cover: Bolt 6x25, Bolt 6x50, Damper,starter Motor Clutch, Screw are included in the Gsx550ef 1987 (h) (e02 E06 E17 E21 E22 E24 E53) Crankcase Cover parts fiche.
On this parts fiche the Bolt 6x25 is the most specified component.
The component with the lowest price in the CRANKCASE COVER schematic is the Pin.