Mountain biking has rapidly evolved since the previous introduction of Shimano’s top level XTR groupset. Shimano sees different directions in mountain biking with wheel sizes and riding styles changing and now defines four main categories within mountain biking. Competitive Cross Country is driven by physical efforts while Enduro focuses on more technical challenges but both have equivalents at the non-competitive Trail level. To serve mountain bikers who will only settle for the best, Shimano today introduces the new rider tuned XTR M9000 groupset. CS-M9000 Cassette Rhythm is the essence of smooth power transfer and a proper gear step is the key to maintaining rhythm over varied terrain. The CS-M9000 11-speed 11-40T cassette is the widest range cassette Shimano has ever produced and also the most balanced. Thanks to its “rhythm step” progression it maintains calculated, shock-free gear steps from one gear to the next, saving riders energy and helping maintain their flow on the trail. Suitable for 3×11-speed drivetrains. Cassette fit to all ten-speed Shimano-compatible freehubs.