Ducati DIAVEL Owner's Manual page 214

Minimum tread depth
Measure tread depth (S, Fig. 164) at the point where
tread is most worn down: it should not be less than
2 mm, and in any case not less than the legal limit.
Important
Visually inspect the tyres at regular intervals for
detecting cracks and cuts, especially on the side
walls, bulges or large spots that are indicative of
internal damage. Replace them if badly damaged.
Remove any stones or other foreign bodies caught in
the tread.
S
Fig. 164
213