Ducati Streetfighter Owner's Manual page 125

The side position of the left beam can be corrected
using the screw (1, fig. 90), on the rear side of the
headlamp. Turn the screw clockwise to move the
beam to the right, counterclockwise to move it to the
left.
To adjust the headlight beam vertically use the screw
(2, fig. 91), on the rear side of the headlamp. Turn the
screw clockwise to lower the beam, anticlockwise to
raise it.
124
1
fig. 90
2
fig. 91