Mountain bikers are psyched, as Shimano's DynaSys11 has been awesome at the XTR level. The XT M8000 components feature 1x11, 2x11, and 3x11 options, and the 11-40,11-42, and 11-46 cassettes broaden the shifting range and gain the 11 speed advantage. The cassettes feature steel cogs, with the exception of the large 40/42/46 tooth cog, which is aluminum, as is the 37t of the 11-46. The aluminum carrier and large cog keep the weight reasonable, and the steel, most heavily used cogs, offer supreme durability. The HG-X11 tooth profile offers Shimano's most advanced shifting integration for smooth, fast up and down shifts under any load.

As with 11 speed XTR, Shimano employed the Rhythm Step progression throughout the cogs, which keeps the 2 tooth step from 11-21, then goes to 3 step for 21 to 24. In the 11-40 cassette, the progression is then 24-27-31-35-40. In the 11-42 it runs 24-28-32-37-42, with the 11-46 the same except for the 46 replacing the 42. Obviously the only large jump is to the final cog, for a true easy-spin, hill climbing effort when required. No special freehub is required, just run your standard Shimano HG compatible 9,10,11.

The 11-42 and 11-46 options are designed for use with the XT 1x11 crankset, and the 11-40 pairs with the 2x11 and 3x11 versions. Please follow Shimano's guidelines for usage. XT cassettes offer an unparalleled combination of shifting performance and durability, which means great value as well. It is virtually impossible to detect shifting difference from XTR, and considering the difference in price, most XTR riders will run XT cassettes for training, saving the lighter, and much more expensive XTR for racing.