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 devicesEngine torque settings
*Dynamic safety-critical point; tightening torque must be within nm +/-5%.
Note
For product specifications and symbols, refer to paragraph "product
specifications" (sect. 1 - 2). ...
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 ...
Coverage
Warranty defects shall be remedied during customary
business hours at any authorized ducati motorcycle dealer
located within the united states of america in compliance
with the clean air act and applicable regulations of the
united states environmental protection agency and the
california air r ...