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 devicesSolenoid starter
Remove the protection cover (a).
Undo the screws (2), taking care to collect the spring washers (3).
Remove the starter motor-solenoid cable (4) and the solenoid-battery cable (5).
Remove the starter solenoid (1) sliding it upwards.
Checking operation of the starter solenoid
To ...
Removal of the front forks
Before removing the front forks, it is first necessary to remove the
following parts:
Loosen the clamp screws (1) holding the fork legs to the steering head (3).
Loosen the clamp screws (2) and (26) securing the fork legs to the bottom yoke
(4).
Withdraw the fork legs (5) and (6) downwar ...
Fuel, lubricants and other fluids
Important
Do not use additives in fuel or lubricants.
Engine oil
A good quality engine oil has special properties. Use only a highly detergent
engine oil with certified se, sf or sg or
higher service ratings as marked on the container.
Viscosity
Sae 15w-50
The other viscosity grades ...