From top-tier XC racing to punishing enduro stages, Shimano defines the rear derailleur with their XTR Shadow Plus 11-speed model. The Shadow design is already well known and loved for its direct cable routing and low profile that greatly lessens the risk of snagging your cable on roots or tagging your derailleur on rocks. Shimano's Plus derailleur technology is a one-way clutch system that stabilizes the cage and your chain when ripping over rough terrain. Chain slap and noise is virtually eliminated and dropped chains are practically a thing of the past. And of course, it retains XTR's legendary smoothness, light action and super precise shifting. The medium-cage design matches perfectly with XTR's double and single ring cranks and 11-speed cassette, offering a crisp, defined gear range.
An important part of a rear derailleur's job is keeping the chain taut as you change gears. Chain-wrap capacity is a number that tells whether or not a derailleur will be able to do this on the drivetrain you plan to use it on. Calculate chain-wrap capacity with this formula: Chain-wrap capacity = (large chainring - small chainring) + (large rear cog - small rear cog). Example: 44/29 chainrings and a 11-28 cassette: (44 - 29 = 15) + (28 - 11 = 17) = 32-tooth chain-wrap capacity.