Parts such as the Crankcase: Nozzle Assy, P1n, Dowel, O-ring (583 Oil Drain Bolt), Bolt, Washer Based(1fn) are included in the Yfz1000r 1997 (v) Usa Crankcase parts fiche.
In this schematic the "Bolt, Washer Based(1fn)" is used most often.
The Bolt, Flange(4my) is the cheapest item from this partsfiche.