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 devicesHow to turn the motorcycle off
To turn the motorcycle off, turn the switch from "run on" to "run off". The
engine stops. To switch the dashboard off,
push the on/off switch downwards. When released, the switch automatically
returns to the "run off" position.
Push the switch downwards to switch the engine off and enter " ...
Refitting 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.
...
Crankcase halves
Bearing
Bearing holder bushing
Alternator-side crankcase half
Bearing
Circlip
Washer
Bearing
Sealing ring
Bearing
Retaining plate
Screw
Screw
Clutch-side crankcase half
Sealing ring
Bearing
Circlip
Bearing holder bushing
Bearing
Plug
Screw
Spacer
Bush ...