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Item # SRM0138

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Item # SRM0138


The SRAM X9 10-Speed Rear Derailleur differs from the 9-speed version in a number of ways. First, the cage width and jockey wheels are sized in accordance with the narrower 10-speed chain. And secondly, it uses Exact Actuation Technology, borrowed from SRAM's road bike shifters, to deliver the most precise shifting possible by ensuring a perfect and consistent shift distance between each gear, all the way across the cassette.

And like the rest of SRAM's rear derailleurs, the X9 Rear Derailleur is designed for a direct cable path from the stop on the frame to the derailleur body, eliminating the typical loop of excess housing to make the junction. This more direct route to the derailleur reduces friction in the cable system and produces a lighter more consistent feel to the shifting.

At a glance, it may be tough to tell this X9 10-Speed Derailleur from the X0 model, but there are differences of course. For one, it's a few grams heavier. Only the short cage version uses carbon fiber for the outer cage plate. The medium and long versions use alloy for both cage plates. The inner and outer parallelogram linkages are also aluminum, with wide pivots to ensure linkage stability when the derailleur is under tension in the biggest cogs. This way, you'll get accurate shifting and quiet performance when pedaling. Also, where the X0 models use sealed cartridge bearings in the jockey wheels, this X9 Rear Derailleur uses sealed bushings. While they'll provide good service, they won't spin with the precision of the bearings on the X0 model, but you'll save a few bucks to spend elsewhere on your bike.

The SRAM X9 10-Speed Rear Derailleur is available with Grey, Red, or White accents and is designed to work with SRAM's 10-speed 11-32 and 11-36 cassettes. It can be paired with one, two, or three chainrings. To that end, there are three cage length options -- Short (DH/single ring), Medium (2x10), and Long (3x10). The mid length cage is suited for use with hardtails and single-pivot suspension designs with minimal chain growth throughout the range of travel. The long cage model can handle the greater chain growth potential that many full suspension trail bikes exhibit. If in doubt, go with the long cage version.

  • Exact Actuation 1:1 ratio means cable movement is equal to derailleur movement, thus providing reliability, easy setup, and effortless actuation
  • Direct Route Technology uses the shortest cable routing possible for reduced friction and weight
  • Carbon cage keeps weight down without sacrificing shifting performance
  • Smooth, freely spinning pulleys keep parasitic drag to a minimum
  • Multiple colors let you dress your little pony up

Tech Specs

high-strength Grilon, aluminum
Cage Length:
short, medium, long
(max) 36 t
Compatible Components:
10-speed Exact Actuation
Claimed Weight:
225 g
Recommended Use:

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Great Derailleur

  • Familiarity: I've put it through the wringer

This derailleur is great. It is pretty lightweight and shifts very well. I've been riding it for the last two years and I've fallen on it many many times. It still shifts great and is really easy to tune when need be.

Good all around

    I run the x9 on all my bikes, they shift well and I dont feel like puking if I break one on the trail (X0 or XX). Paired with a X9 shifters they do what you ask them to and last!

    Good all around

    A little X0 and a little X7...

      The X9 is a nice step above the X7 but I'd spend a few quid more for the X0 stuff as the difference over X7 isn't as substantial. These are great and look the part but not enough better than X7 to justify much of a premium in my opinion. Had these on my last niner hardtail and they worked great.