Shimano GRX RX 815 Series Dealer's Manual page 67

INSTALLATION/REMOVAL
Temporarily installing the front derailleur
2.
Install the band adapter to the front derailleur.
(1) Refer to Step 2 of "When there is a mounting boss on the frame" to attach the
backup plate to the band adapter.
(2) Install the band adapter to the front derailleur.
3.
Tighten the support bolt until it touches the backup plate.
Band adapter
Band adapter
Support bolt
67
Mounting bolt
5 - 7 N·m