Ducati MONSTER 821 Workshop Manual page 903

Work on both intake manifolds and tighten screws (1) to a torque of 10 Nm (Min. 9 Nm - Max. 11 Nm).
Apply specified threadlocker on the vertical head union (8).
Fit seal (9) and tighten union (8) to a torque of 2 Nm (Min. 2 Nm - Max. 3 Nm).
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