Ducati DIAVEL Owner's Manual page 169

To change preload of the spring inside each fork leg,
turn the hex. adjuster (2, Fig. 119) with a 22 mm
hexagon wrench, starting from the fully open
(clockwise) position.
From reference (A, Fig. 119), every full turn clockwise
corresponds to 1 mm of preload of the spring, up to
a maximum of 15 mm, corresponding to 15 full turns.
STANDARD settings from completely closed are as
follows:
- compression: 1 and a half turns;
- rebound: 1 and a half turns;
- Spring preload: FULLY OPEN.
Warning
Adjust both fork legs to same settings.
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