Ducati ST4s Owner's Manual page 147

To set the rear brake pedal,
6
loosen check nut (4).
7
Turn pedal travel adjusting screw (5) until pedal is in the
desired position.
Tighten check nut (4).
Work pedal by hand to make sure it has 1.5 - 2 mm free
play before brake begins to bite.
If not so, set the length of cylinder linkage as follows.
Loosen the check nut (6) on cylinder linkage.
E Tighten linkage into fork (7) to increase play, or unscrew
linkage to reduce it.
Tighten check nut (6) and check pedal free play again.
5
4
fig. 26
38