• 01-01-2020
    Erik_A
    2 Attachment(s)
    Shimano GRX ST-RX400 shifter (10 sp) compatible w/ XT RD-M786 (10 sp) rear derailleur
    Is the new Shimano GRX ST-RX400 shifter (10 speed) compatible with the old mountain XT RD-M786 (10 speed) Shadow+ rear derailleur?


    Attachment 326647
    Attachment 326649
  • 01-01-2020
    Erik_A
    What I have discovered is that all 3 GRX groups (RX400, RX600, and RX810) are all based on the Shimano "road" 11 speed derailleurs (just the RX400 is 10 speed but with a pull ratio like Tiagra 4700 which is different than other 10 speed Shimano).*

    See: https://productinfo.shimano.com/#/co...-441&cid=C-432

    Also, a RX400 rear derailleur can also be used on any Shimano 11 speed road shifter.