Ducati MULTISTRADA 1200S ABS 2015 Workshop Manual page 672

Fit the bottom yoke assembly to frame.
Grease the ball race (B) and fit it to the upper outer ring (8) of the frame.
Fit the inner ring (A) of the upper bearing (6) to the steering head, with the larger diameter side of the race facing
upwards.
Install the sealing ring (5) with the flat side facing upwards.
Tighten the adjuster ring nut (3) by hand until it seats against the sealing ring (5).
Fit on ring nut (3) the special bush (C) part no. 88713.1058 and fit the torque wrench on it.
Apply recommended threadlocker on thread and tighten adjuster ring nut (3) to 35 Nm ±5%.