GRX RX600 shifter with Deore XT rear derailleur ok?

My wife wants a bike that has the 1x11 GRX groupset but the gears are 40/11-34 and she would most probably need a 1:1 ratio or even more.

I am thinking of replacing the GRX rear derailleur (GRX RX810 GS. Max 34T) with a Deore XT (RD-M8000 GS. Max 46T in 1x11) so that she can have a 40, 42 or even 46T together with the 40T in the front.

I am assuming that the Deore XT RD-M8000 GS rear derailleur works with the Shift-/ Brake Lever GRX RX600 (both 11 speed)......Am I right???

Shimano uses different pull ratios for road and mountain derailleurs so you will need a tanpan to make it work.

https://www.wolftoothcomponents.com/collections/drivetrain-1/products/tanpan?variant=18367738757

Wolf Tooth's Roadlink DM will get you to the 42t.

barturtle wrote:Wolf Tooth's Roadlink DM will get you to the 42t.

together with the RD-810?

TonyM wrote:

together with the RD-810?

"Optimized for use with GRX ultra wide range drivetrains when using the GRX 810 (RX810) rear derailleur"

https://www.wolftoothcomponents.com/products/roadlink-dm

barturtle wrote:

"Optimized for use with GRX ultra wide range drivetrains when using the GRX 810 (RX810) rear derailleur"

Great! 

So I have therefore now 2 options:
- Roadlink/ RD-GRX810
- RD-GRX812

I will ask Wolftooth if the Roadlink also works with the RD-GRX812.

812 can do up to 46t with no issues from the videos I have seen. 

RideWithPride wrote:812 can do up to 46t with no issues from the videos I have seen. 

Good to know! That matches what dangle said :-)

Something I recall from homework and an ask I made here was the XT still has a larger overall teeth capacity that might not be pertinent here because 1x is stated.