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 devicesChecking valve lift
Set the engine to the configuration described for the "checking and adjusting
the valve clearances", previously indicated.
Position the tool 88765.1518 On the cylinder head: the part marked "a" should be
on the intake side and the part
marked "s" should be on the exhaust side.
Seat the pl ...
Refitting the gearchange mechanism
Make sure that the gearchange linkage assembly (6) is installed with the ball
joint with a left-hand thread (a) facing the
lever (8).
Apply the recommended grease to the non-threaded surface of the pin (4).
Fit the first o-ring (5) in the pin (4).
Start the pin (4) in the gearchange leve ...
External components
Oil breather valve
O-ring
Sealing washer
Gear position sensor
Cylinder barrel/head stud
Nipple
By-pass spring
Plug
Plug
Aluminium gasket
Nut
Lock washer
Timing gear pair
Key
Key
O-ring
Screw
Locating dowel
Starter idler gear
Washer
Gear shaft
O-ring
...