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Shimano XTR RD-M9120 Rear Derailleur Shimano XTR RD-M9120 Rear Derailleur
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XTR RD-M9120 Rear Derailleur

Mfg PartNum:IRDM8120SGS
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XTR - Rear Derailleur - Medium Cage - SHIMANO SHADOW RD+ - 2x12-speed

The XTR M9100 series of derailleurs brings a new level of drivetrain silence thank to decreased tension in the low gear position and an added bumper on the pulley cage. Larger 13T pulleys increase efficiency and chain management while compatibility with SHIMANO's new 12-speed cassettes boosts range.


  • 10-45T (1x12-speed)
  • Decreased rear derailleur tension at low gear position, to prevent high chain tension
  • Add bumper at rear derailleur pulley cage
  • Bigger 13T pulley
  • 10-45T (2x12-speed)
  • Enhance shifting performance
  • Silent drivetrain
  • Low profile design
  • Low sprocket compatibility

  • B-Stock - This product has one or more B-Stock units available. These units can be purchased at a discount (see option select). B-Stock units were returned from other customers and may have missing or damaged packaging materials. These units are otherwise as new. The full manufacturer warranty applies. Click Here for more information.

    The product weight specified is an approximate weight based on the manufacturer's specifications (if available) or our measurement of one or two examples. For most products, the weight will typically vary by 5% to 10%.


    Mfg PartNum: IRDM9120SGS 


    Material: Aluminum 


    Capacity: 2x 10-45t 12-speed cassette 


    Gearing: 2 x 12 


    Compatibility: [chain] XTR CN-M9100, [cassette] XTR CS-M9100, [shifter] XTR SL-M9100-R, XTR SL-M9100-IR, [front derailleur] XTR FD-9100-M, XTR FD-9100-E, XTR FD-M9100-D 


    Weight: 241 g


    Discipline: mountain biking 


    Mfg PartNum: RD-M9120-SGS 


    Series: XTR M9100 Series 

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