Ducati Diavel Workshop Manual page 358

Diagnostic instruments
The socket to which the cable (Measurement Module) (4) is to be connected is indicated on the screen with a capital
letter: A, B or C.
Turn over the engine with the starter motor until the pressure stops rising.
Check the pressure in each cylinder:
- standard value: 11 to 12 bar;
- minimum value: 10 bar;
- maximum permissible difference between cylinders: 2 bar.
An excessively high pressure value can be caused by:
- build up of deposits in the combustion chamber.
An excessively low pressure value can be caused by:
- gas escaping between the cylinder head and the barrel;
- worn valve seats;
- bent valve stems;
- incorrect valve clearances;
- worn cylinder or piston rings.
Refit the spark plugs and position the coil-spark plugs wires (1) in the corresponding compartments and tighten the nuts
(2) to a torque of 10 Nm (Min. 9 Nm Max. 11 Nm) (Sect. 3 - 3, Frame torque settings).