Ducati Diavel Carbon Owner's Manual page 183

To change preload of the spring inside each fork leg,
turn the hex. adjuster (2, Fig 127) with a hexagon
wrench of 0.87 in (22 mm), starting from the fully
open (clockwise) position.
From reference (A, Fig 127), every full turn clockwise
corresponds to 0.04 in (1 mm) of preload of the
spring, up to a maximum of 0.59 in (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.
Attention
Regulate the adjusters on both legs to the same
positions.
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