Ducati ST4s 2001 Manuel De L'utilisateur page 109

Warning
The shock absorber is filled with gas under
pressure and may cause severe damage if taken apart by
unskilled persons.
Important
When carrying a passenger and a load, 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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