Ducati Diavel Carbon Owner's Manual page 205

Brake system
If you note too much play on brake lever or pedal and
brake pads are still in good condition, contact your
Ducati Dealer or Authorized Service Center to have
the system inspected and any air drained out of the
circuit.
Attention
Brake and clutch fluid can damage paintwork
and plastic parts, so avoid contact.
Hydraulic oil is corrosive; it may cause damage and
lead to severe injuries. Never mix fluids of different
qualities. Check seals for proper sealing.
Attention
Hydraulic oil 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 too much play 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 Authorized Service
Center 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 above the minimum level).
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