Parts such as the Swingarm: Shaft Assy.,prop., Ring Damper Cover, Nut,rr.fork Pivot, Stopper,damper Li are included in the St1100 1991 (m) Usa California Swingarm parts fiche.
This schematic depicts all components used in the St1100 1991 (m) Usa California Swingarm partslist.
This SWINGARM assembly utilises four Nut,hex.,10mm(s) - the highest specified component.