Give your friends $10

Shimano XTR Di2 RD-M9050 Rear Derailleur

Sale $388.99 $572.99 32% off

Item # SHI005I

Select options
  • Select options
  • Black, Medium Cage ($388.99)
  • 100% Guaranteed Returns
  • Free Shipping on orders over $50

Item # SHI005I

Smart aft.

Shimano's XTR Di2 RD-M9050 Rear Derailleur's coolest feature is definitely Shimano's Synchronized Shift system. You might think effortless, perfect-in-all-conditions shifting that's never compromised by wear and contamination would trump any entrant in this category, but, well, it doesn't. We even admit to being skeptical at first, since Synchronized Shift automatically shuttles your chain from cog to cog without any input from you, but the results of just one ride on this system speak for themselves. The RD-M9050 intelligently manages the fleet of cogs at the aft-end of your drivetrain.

By putting the rear and front derailleurs in communication with each other, Synchronized Shift can actually calculate your efficiency and perform simultaneous front and rear shifts to eliminate cross-chaining and set you up in the best chain line for any given gearing. These shifting patterns depends on the direction you're shifting and the combination you're shifting into, and they're also programmable via Shimano's E-Tube system, so you can set your preferences in advance to ensure that your internally-communicating drivetrain isn't conspiring against you.

Another category of big winners in the Synchronized Shift game are short cage derailleurs, which the system protects by making sure you never run out of chain when cross-gearing; it just adjusts the front and the rear to give you the gearing you want without tearing your derailleur off. Still, if you decide against Synchronized Shifting, then you can turn it on or off as your preference demands.

The shifting itself is peerless, as the derailleur always knows where it is, so its travel isn't restricted or lengthened by imperfect cables. It situates the chain squarely on every cog and it jumps between those positions with startling speed. No hesitation, no grinding. Ever.

As with other Shimano Di2 bits, the XTR rear derailleur is compatible with Shimano's rust-, stretch-, freeze-, and generally worry-free E-Tube wiring system. Its modularity makes it easy to set up on virtually any frame, though it does cohabitate with less friction when the frame is built with Di2 in mind.

  • Synchronized Shift technology
  • Shifting pattern can be programmed to your preferences
  • E-Tube wiring system

Tech Specs

3 x 11, 2 x 11, 1 x 11
Claimed Weight:
[pair] 128 g
Recommended Use:
Manufacturer Warranty:
2 years

Reviews & Community


Write a review

    Add a:
  • Photos
  • Videos

No file chosen

Rather attach a photo from your computer?


Only jpg, jpeg, png, gif or bmp files please.

Submit ReviewCancel
Unanswered Question

Weight is wrong - per Shimano's site it's 289-292g

I want to run a 1x 40T front, 11-40 rear. Will a medium cage xtr work?

Yes, the medium cage works with single and double chainring setups with the current generation XTR.

Bradley Gehrig

Customer Account Manager

Office: 801–204-4541

Great for CX 1x

  • Familiarity: I've put it through the wringer

Really happy with this RD. I have it on a CX bike set up with a 1x and it works really well. I had a DuraAce RD with a RoadLink but the XTR clutch handles the big range much better without any chain issues.

Super awesome !

  • Familiarity: I've used it once or twice and have initial impressions

Have Dura Ace Di2 11-speed on the road steed, now rolling with it on my mt steed :) Total FYI - I am running a SRAM 10-42 cassette, SRAM chain, and SRAM Xo1 1X cranks with this - works flawlessly! I had many hesitations because I love the 1X drivetrain SRAM has to offer as well as the hill grinding 10-42 cassette. Setting up is waaaay easier then running cables, etc.
Only hard part is, that depending on your frame, where to put the battery and wires. Pre-planning wiring and battery placement is a must prior to install. I have a 2015 Stumpjumper FSR 650b and was able to locate the battery in in the seat tube, just below the dropper post. For the short runs of wires that are exposed, I used electrical shrink-wrap tubing for a super clean look.
Long term test to follow. I am familiar with the E-Tube set-up and set the rear derailleur to 'fast' - awesome. Also, if you run Di2 on your road bike, the front LED Display already has a junction box, so no need for that. Additionally - if you get the new FOX shocks, you can remotely actuate the shock setting with this stuff also - super crazy.