Ducati Diavel 1260 Owner's Manual page 317

Attention
Brake and clutch fluid can damage paintwork
and plastic parts, so avoid contact.
Hydraulic fluid is corrosive; it may cause damage and
lead to severe injuries. Never mix fluids of different
qualities. Check seals for proper sealing.
Clutch system
If the control lever has exceeding clearance and the
transmission snatches or jams as you try to engage a
gear, it means that there might be air in the circuit.
Contact your Ducati Dealer or authorised Service
Centre to have the system inspected and air drained
out.
Attention
Clutch fluid level will increase as clutch plate
friction material wears down. Do not exceed the
specified level (3 mm - 0.12 in above the minimum
level).
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