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 devicesDucati limited warranty on emission control system
Ducati north america, inc., 10443 Bandley drive cupertino,
california, 95014 warrants that each new 1998 and later
ducati motorcycle, that includes as standard equipment a
headlight, tail-light and stoplight, and is street legal:
a) is designed, built and equipped so as to conform at the
time o ...
Protective apparel
Always wear a helmet. Most motorcycle accident fatalities
are due to head injuries.
For safety eye protection, gloves, and high top, sturdy boots
should also be worn.
The exhaust system becomes very hot during operation,
never touch the exhaust system. Wear clothing that fully
covers your ...
Front brake lever
Pull the lever (1, fig. 94) Towards the twistgrip to operate the
front brake. The system is hydraulically assisted and you only
need to pull the lever gently.
The control lever (1, fig. 94) Features a dial adjuster (2, fig. 94)
For lever distance from the twistgrip on handlebar
adjustment.
...