The twenty-seven Z550g3 Gt550 1986 United Kingdom Fg Front Master Cylinder component parts are all listed in this schematic.
On this parts fiche the Washer,10.5x15x1.5 is the most specified component.
Some items from this specific schematic: Bolt-upset-wp, Hose-brake,fr, Cover-seal,brake Pist, Holder-brake,master C.