thirteen components are listed in the schematic for this Cbr600f Hurricane 1987 (h) Sweden / Kph Gasket Kit B .
Some items from this specific schematic: Washer,sealing,6., O-ring 13x3.0, Washer,plug,drain 12, O-ring 32.95x2.62.
On this parts fiche the O-ring 13x3.0 is the most specified component.