Ducati MONSTER 821 Workshop Manual page 1151

Warning
The grease utilised is irritant in contact with the skin; wear protective gloves.
Important
Lubrication of con-rod bolts is essential to obtain the correct coupling and to prevent breakage of the parts.
The con-rod screws may only be used for one tightening.
Tighten the screws (3) fully home by hand.
If this proves difficult or if the screws jam, undo them and lubricate them again.
Remove any excess grease. Tighten the screw by hand until the head seats against the connecting rod.
Temporarily fit the gudgeon pin (L) to align the connecting rods.
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