The negative cable, which is normally connected to the negative pole of the battery, is fastened to the crankcase. From here, the cable branches off and splits up within the electrical system to carry the ground connection to the different elements in the system.

The image shows the ground connection on left side of the engine crankcase.
The battery charging circuit and power distribution
Electrical power for lighting and signalling devicesRefitting the seat
Note
Apply recommended grease to the hole (a) of latch (6).
Fit the seat (1) as follows: insert the tabs (b) (on the front side) under
the rubber pads (c) of the gloves compartment;
then push the seat rear side until hearing the lock latch click.
...
Removal of the control unit
Loosen the screws (1) and remove the relay supporting bracket (2), disconnect
the connectors (3) and remove the control
unit (4) from the vehicle.
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Tail light - number plate holder
Rh tail light
Vibration damper mount
Spacer
Screw
Number plate light
Screw
Screw
Plate
Number plate holder
Nut
Screw
Rear chain guard
Lh tail light
Spring washer
Vibration damper mount
Splashguard
Screw
Spacer
Screw
Washer
Splashguard (europe - australi ...