Parts such as the Cam Chain - Tensioner: Bolt,flange,6x16, Sprocket,cam, Washer,lock, Collar,7x13.2 are included in the Cx500c Custom 1980 (a) Italy Cam Chain - Tensioner parts fiche.
On this parts fiche the Bolt,flange,6x16 is the most specified component.
The Honda CAM CHAIN - TENSIONER has twenty-two products enlisted in the schematic.