Ducati SCRAMBLER 800 Workshop Manual page 364

Fit the rear wheel (Refitting the rear
wheel).
Tighten special screw (1) with the two seals (3) to a torque of 23 Nm ± 10%.
If previously removed, fit speed sensor (6) with spacer (8) and tighten screw (7) to a torque of 7 Nm ±
10%.
Check the Air-Gap (Adjusting the phonic wheel sensor
AIR-GAP).