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 devicesInstrument panel on handlebar
Lcd.
Neutral light n (green). Illuminates when the gearbox is in neutral.
High beam light (blue).
It turns on to indicate that the high beam lights are on.
Engine oil pressure light
(red).
Illuminates when engine oil pressure is too low. It must turn
on at key-on, but ...
Spark plugs replacement
Check the colour of the ceramic insulation around the central electrode:
an even, light brown colour indicates the engine is in good condition and
running at the right temperature.
Inspect the centre electrode for wear and check spark plug gap, which should be:
0.8+/-0.1 Mm.
Important
...
Checking and topping up coolant level
Check coolant level in the expansion tank on the right side of
the vehicle.
Steer the handlebar completely to the left and check that the
level is between the min and max marks on the side of the
expansion reservoir.
Top up if the level is below the min mark.
Unscrew the filler plug (1) ...