Ducati MONSTER S4 Owner's Manual page 27

Standard factory setting is as follows:
compression: 12 clicks;
rebound: 11 clicks.
The max. setting range is 14 clicks (rebound) and 14
clicks (compression) that ensure the softest damping.
To change the preload of the spring inside each fork leg,
turn the adjusting nut (2) with a 22-mm hexagon wrench.
Preload setting range (A) is from 25 to 10 mm
Factory setting is 16 mm.
Important
Adjust both fork legs to same settings.
1
3
2
A
fig. 17
fig. 18
27
E