Overhauling The Piston - Ducati MONSTER 821 Workshop Manual

Overhauling the piston

Clean the piston crown and piston ring grooves, removing any carbon deposits.
Visually inspect the piston and check its dimensions carefully: there must be no signs of scuffing, scoring,
cracks, or other damage.
The piston diameter must be measured at 7.5 mm up from the bottom of the skirt and in perpendicular
direction to the gudgeon pin axis.
The pistons must always be replaced as a pair.
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