Shimano ALFINE S7051 Series Dealer's Manual page 94

MAINTENANCE
In the case of 11-speed internal geared hub (Oil maintenance kit: Y13098023)
6
While performing gear-change operations, turn the pedals to turn the wheel for about 1
minute.
7
Keep the wheel still without rotating for about 1 minute.
8
Remove the oil from inside by following the procedures in Draining out the old oil above.
Injecting new oil
1
Inject 25 ml of new oil into the hub by following steps Cleaning the inside 1 - 5 above.
2
Clean off any oil that may have gotten on the hub, etc.
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