Parts such as the Crankcase: Drain Cock, Crankcase Comp. L., Bolt,flange,6x50, Clamper,tube are included in the C50lm Little Cub 1999 (x) Japan Crankcase parts fiche.
On this parts fiche the Bolt,flange Sh 6x65 is the most specified component.
The fourteen C50lm Little Cub 1999 (x) Japan Crankcase component parts are all listed in this schematic.