Ducati MONSTER 821 Workshop Manual page 595

Lubricating the chain
O-ring chains have sealed, life-lubed link studs and bushes.
However, these chains need to be lubricated at regular intervals to protect metal parts of the chain and the
O-rings.
Lubrication also serves to keep the O-rings soft and pliable to ensure the maximum sealing efficiency.
Using a brush, apply a thin protective layer of high-density gearbox oil along the entire length of the chain
both inside and outside.
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