We've all been there, grinding slowly up a never-ending climb as our cadence slows to a high-torque, barely moving crawl, fruitlessly clicking the shift lever in hopes that an ethereal body will drop out of the sky and deliver an extra cog to lighten the pressure. Airborne deities notwithstanding, SRAM swoops in with its Eagle one-by 12-speed drivetrain. Eagle's gear range rivals that of a two-by system without the extra weight and worry of a finicky front derailleur. The SRAM XX1 Eagle 12-Speed Rear Derailleur brings the system together, driving precise gear changes across the entire cassette with a titanium spring and carbon fiber outer cage.
Similar to SRAM's one-by 11-speed offerings, this little derailleur holds a heap of technology bent on creating a pleasant riding experience with clean shifts and no unnecessary noise distracting from the outdoor ambiance. The Roller Bearing Clutch, long revered for its nearly unbeatable chain stabilization, gets an update with a repositioned upper pulley and larger lower pulley to accommodate the extra chain length needed to run such a wide range of cogs. Paired with a strengthened clutch, it efficiently manages chain tension to eliminate derailleur bounce and chain slap for a solid, noise-free ride. X-Horizon further boosts this stability by limiting movement across the horizontal axis, with its large upper pulley design maintaining a constant chain gap across the cassette. This effectively reduces shift initiation force and eliminates pesky ghost shifting, so you'll drop into the right gear with minimal effort the second you want it.
Last, but by far not the least, is SRAM's Exact Actuation technology. Exact Actuation addresses the issue of different gears requiring different amounts of cable pull to shift, which in turn leads to loud cassettes and inefficient shifting. With Exact Actuation, each gear shift requires the same amount of cable pull, resulting in a predictable click and shift no matter where the chain sits in the cassette. This also means an overall quieter, better adjusted drivetrain for predictable shifting in any situation.
Shredding trails comes with its fair share of mechanicals, and the SRAM XX1 Eagle 12-Speed Rear Derailleur makes wheel swaps and maintenance a breeze with a slight update to SRAM's Cage Lock design that sees the lock pin tucked a bit more out of the way and more protected from trail debris than previous iterations. Functionally, it remains the same—just push the derailleur forward and it locks into place for quick and easy rear wheel removal or installation to get back out on the course in a snap.
- The sole derailleur in SRAM's Eagle drivetrain
- Updated pulley design accommodates extra chain length
- Exact Actuation guides precise shifts
- Impeccable chain stability
- Cage Lock makes wheel swaps a breeze