Ducati SPORTTOURING ST3 Manuel D'utilisation page 144

Warning
Use a specific pin wrench to turn the preload
adjusting nut. Be careful when turning the nut with the
wrench, as the pin may slip out of the ring nut recess and
you may hurt your hand hitting motorcycle parts.
Important
The shock absorber is filled with gas under pressure
and may cause severe damage if taken apart by unskilled
E
persons.
When carrying a passenger and luggage, set the rear
shock absorber spring to proper preload to improve
motorcycle handling and keep safe clearance from the
ground. You may find that rebound damping needs
adjusting as well.
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