It Works!! // The $127 Shimano GRX Mullet Upgrade

No Goat Links, no Tanpans, no 3rd party mods. An all-Shimano solution to an affordable, reliable, 11 speed GRX mullet setup for up to 10-51t cassettes.

The GRX RX822 SGS 12 speed rear derailleur is compatible with GRX 11 speed shifters like GRX 600 and GRX 800. You install the RX 822 like any other derailleur, but max out the high limit screw, which limits it to 11 speeds. You will likely need a longer chain to go with your wide range cassette of choice. This video features an 11 speed Deore 11-51T MTB cassette.

Shimano GRX RD-RX822 SGS 12 Speed Rear Derailleur:

Shimano CS M5100 11-51t 11 Speed Cassette:

Check out Maverick Cycles if you're nearby in Whittier, CA

Credit to drinksta who posted this in the r/gravelcycling subreddit a couple months ago:

[michiganstate]

This worked super well for me. GRX 11s shifters. Garbaruk 10-50 11s XD. Eagle XX1 12s chain. Shimano GRX 822 SGS 12s derailleur. Absolute Black 42t chainring. Shifts super well. Better than my Eagle MTB Garbaruk setups. Love this combination on my gravel bike.

Caveat: check your B limit. I found that matching the line on the derailleur (meant for a 51t) to the 50t Garbaruk was spot on. The other thing. Use the Shimano recommended chain length (4-5 links+ quick link on big to big). I cut mine too short (2 links, vs the 4) and it skipped on the 10t cog while riding. With the right length it shifts better and no skipping.

[jonruble]

I wanted to try this, but multiple mechanics told me it wouldn't work. In my mind, it made total sense, but they kept telling me that the grx 822 sgs pull ratio wouldn't allow it. Thanks for confirming my hackster suspicion.

[mustardlightning]

Actually, on a lot of frames this can be done with an 11 speed GRX812 and a 5100 series MTB cassette. And with a WolfTooth Roadlink with virtually any frame. Tried and tested. Cost me a total of 60€.

[kornelius]

I am also among those who were lucky to get it to work properly fairly easily. I was hesitant at first, but really wanted to get rid of WolfTooth Tanpan with deore derailleur combination. So I went ahead and ordered the GRX one. Been riding it for over 3 months now. And It just works. Without any hiccups

[TG-lpyd]

It works for me!
Grx 600 duals, rd 822, 11-46 slx and hg-701 chain

[Fango]

My only issue with GRX 11speed was the low cassette capacity - this solves the issue of having to buy new wheels (or a new freehub) to go to the range of 12 speed. Great solution, probably gonna put this on my bike once the cassette is worn!

[DailyBag]

Glad to see the pull ratio is almost the same 💯

[stevekelly]

The Maverick Reynolds 725 gravel frames look really nice- their single speed bike is nice too.

[DETarch]

Thank you for providing another compatibility data point (with supporting video evidence!) of this combination. There are a few instances of folks doing it on Reddit, and based on those, I just grabbed an RX822 for this same setup, but with GRX400 10 speed brifters paired to an 11-48 Microshift 10 speed cassette. I've got a Garbaruk cage on an RX812 currently which works fine, but glad to have more options!

[roypennock]

My LBS did a conversion on my 2023 Marin Gestalt XR (standard GRX 800 1x, 11-42 11 speed w/ 42T chainring) at time of purchase using a M5100 11-51 cassette, Deore RD-M5100 derailleur, a CN-HG601-11 Shimano chain (OEM was KMC) and a Tanpan on an exchange basis so it only cost me about CDN $100 after the parts credit. I am coming into 700c wheels and drop bars after 35 years of casual 26" flat bar MTB riding and I can say I'm very happy with the results so far!☺

[Tuehl]

Great Video. Followed the guidance and converted my bike to this 11 speed mullet with the bigger 51T cassette. It’s awesome 😊😊😂

[inkognitobi]

Cool Idea, thanks for the informative Video and testing. However, the cheapest all-Shimano option wasn't even mentioned so far.
You can swap the cage on a 11-Speed RX812 for the SGS-Version of the 11-Speed Deore XT one (M8000 Series). Inner and outer Cage plate should be about 15-20$ retail. Works great on a 11-51 Deore Cassette for me.
I was originally looking into the Gabaruk cages, but this seems to be the cleaner and cheaper solution.

[pieterlyssens]

Great job love the videos always looking forward for the next.
I’ve been riding the Grx 812 11speed straight from the box with the deore 11-51 for 3 years no issues.
I saw your video immediately ordered a 822 long cage and gave it a try for my next build but the grx 822 didn’t work.
I worked on it a few hours a day for a week and ended up buying the 812 again.

[FlipperInc]

For those w sora 9 speed shifters you can run an mtb 9 speed rear derailleur

[pipi]

Same Thing should work with 10 speex GRX parts. A GRX 400 brifter can shift an 11 speed GRX 1by rd. But only for 10 speed cassettes ofc

[Gregorius]

0:49 The pull-ratio of MTB and road Shimano rear shifters was compatible until 9 speed. Even a 10-speed road brifter (except Tiagra 4700 and 10s GRX which is compatible with 11 speed) can be used with a 10-speed cassette and a 9 speed rear shifter.

[ukasz]

Whoa, that's good news! I'm building a new bike and brainstorming drivetrain options right now. I guess I will go the same route as you did and couple R7000 brifters but mix 12-speed GRX derailleur instead. Looks like that would be $400 for the whole thing (I already have a GRX crankset) which is really nice.

[SHWELL]

This video answered my question asked on another video today. Thank you!

[jmdrstv]

When I had GRX 11 spd I went with a e13 Helix 9-46 and a smaller chainring and it was flawless, light and no other mods.

GRX is a great group. Still my favorite hoods and brifters

[jeremywishart]

This is AWESOME! Thanks for testing and posting this. Just ordered all the parts.