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Sram XX1 Eagle B1 Rear Derailleur 12-speed 52t



Occupying a new realm in shifting performance, the redesigned XX1 Eagle B2 rear derailleur gives no-compromise racers and dream-bike builders a true top-tier option. The crisp, precise XX1 shifting feel athletes rely on now features an updated cage geometry for improved chain management. Occupying its rightful place at the top of the Eagle ecosystem, the XX1 Eagle rear derailleur makes full use of the new 10-52t cassettes and is backwards compatible to also work with the 10-50t.


  • Updated cage geometry provides better chain retention and crisper shifting.
  • Backwards compatible, works with 10-50t and new 10-52t cassettes.

  • CABLE PULL RATIO: X-actuation
  • SPEED (RD): 12s
  • COLOR (RD): Lunar
  • MAX TOOTH: 52

Model Number
Item Code
Sram XX1 Eagle B1 Rear Derailleur 12-speed 52t