Shimano GRX RX 815 Series Dealer's Manual page 111

INSTALLATION/REMOVAL
Installing the brake hose
7.
Remove the lever stopper.
Pull out the lever stopper by means of short back and forth movements. Take care to not
depress the lever.
NOTICE
• After removing the lever stopper, check that the pad spacer is installed on the
caliper side and that the caliper is installed on the bicycle with the disc brake
rotor between both sides of the caliper before depressing the lever. After
installation to the bicycle, make sure to check that the lever stopper is removed.
8.
Check that the lever has become stiff.
If it does not become stiff, refer to the procedure in "Adding mineral oil and bleeding
air" to bleed the air.
Lever stopper
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