Ducati MONSTER 821 Workshop Manual page 934

For vertical head only: tighten stud bolt (1A) with the special tool.
Tighten the three stud bolts (1) and (1A) to a torque of 10 Nm (Min. 9 Nm - Max. 11 Nm) so that reference
point (B) is clearly visible.
The intake side can be identified by the presence of four threaded holes on the flange.
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