Since its introduction in 1991, the abbreviation XTR adorned Shimano’s lightest and highest quality groupset, and now the component giant has released the latest iteration of their high-end groupset. The Shimano XTR M9100 is Shimano’s first 12-speed drivetrain, and with its new wide range cassette, it’s perfectly in line with the 1×12 trend.

The demand for wide range 1x drivetrains has risen continuously over the last few years, and manufacturers are increasingly abandoning the front derailleur option on their bikes. At the latest, since the introduction of the SRAM Eagle groupset more than two years ago it has become clear: the front derailleur is outdated on (almost) all mountain bikes. The new Shimano XTR M9100 is still available as a 2x drivetrain, but the star of the show is the new 10-51T cassette. With a 510% gear range and even gear steps, the most die-hard 1x critics should start to falter.

“Speed, focus and control were the words we lived by during the development phase. We’ve designed new XTR to enhance acceleration and speed by drastically cutting the loss of driving force with a redesigned drivetrain. We allow for precision focus with an intuitive handlebar set up and pinpoint control comes with new brake solutions. XTR is not an update of M9000, it’s a redesign from the ground up to find the best components for MTB racing for XC, Marathon and Enduro racing.”
Bas Van Dooren, Shimano Europe Product team leader

Depending on the configuration the new Shimano XTR M9100 can save up to 150 g to its predecessor but the higher range and stronger brakes will be more relevant to trail riders. The table shows the weights compared to the previous XTR M9000:

XTR M9100 XTR M9000
Cassette 359 g (11-51T), 349 g (10-45T), 299 g (10-45T 11-speed) 330 g (11-40T)
Rear derailleur (long) 240 g 224 g
Shifter (I-SPEC) 117 g / 74 g (R/L) 200 g (pair)
Cranks (32T) 511 g 598 g
Chain 242 g 247 g
Brakes (203 mm rotor) 385 g (149 g) 360 g (173 g)
Hubs 138 g / 231 g (F/R) 155 g / 277 g (F/R)

Shimano XTR M9100 Cassette

The heart of the new groupset is the 12-speed cassette with a 510 % gear range. With the 10-51T cassette, Shimano riders can finally enjoy a high gear range with smooth gear steps (10-12-14-16-16-18-21-24-28-33-39-45-51T) even with a 1x setup. The elaborate cassette is made of various materials to achieve the perfect compromise between weight and durability. The biggest sprockets are made of aluminium, the middle ones of titanium and the smallest ones of steel. To accommodate the smaller 10T sprocket, Shimano has introduced a new freehub body called the MICRO SPLINE. Moreover, there is a 12-speed chain to match the new drivetrain, which, for the first time, comes with a quick link.

For XC racers or riders who prefer smaller steps between gears, there is a 10-45T cassette (10-12-14-16-18-21-24-28-32-36-40-45T). As an alternative to the two 12-speed cassettes, Shimano offers another option designed for hubs with wider flanges and a narrower freehub body. Based on the 10-51T cassette, but without the large 51T sprocket, this 11-speed cassette is fully compatible with the 12-speed components, but is narrower and lighter.

Shimano XTR M9100 rear derailleur

The XTR M9100 rear derailleur, with its new design with anodised aluminium surfaces, is an eye-catcher. Large pulley wheels with 13 teeth are designed to improve shifting performance and, in combination with the Shadow RD+ clutch, contribute to better chain retention. There are specific medium (10-45Z) or long cage (10-51Z) derailleurs available for 1x drivetrains.

Shimano XTR M9100 shifter

The XTR M9100 shifter has taken over proven features from its predecessor, such as RAPIDFIRE Plus, 2-WAY RELEASE and MULTI-RELEASE, but is designed to make shifting even easier and more intuitive thanks to reduced shifting force and fingertip movement. The new shifters can be attached directly to the brake lever mount via I-SPEC-EV. Not only ensuring a tidy cockpit but also providing plenty of adjustment possibilities that allows riders to adjust the position of the shifter to their own needs and preferences. The shifters can be moved 14 mm horizontally and rotated by 60°. The new dropper remote is also I-SPEC-EV compatible with dropper seat posts where the cable is clamped at the seat post, such as the in-house PRO Koryak. Riders sticking with their 2x setup can look forward to a completely revamped mono gear lever, which makes use of a single lever to change between the large and small chainrings.

Shimano XTR M9100 Crank

The new XTR crankset is based on Shimano’s typical hollow-forged aluminium crank arms and is available with chainrings from 30 to 38 teeth. Compared to the previous version, the new crank saves 80 g in weight. Shimano is also debuting its own chain guide for E-Type, D-Type or ISCG 05 mounting. If you are looking for maximum gear range, you also get a 2-speed crank with 38/28 teeth, which can be combined with the 10-45T cassette.

Shimano XTR M9100 Brakes

While XC riders can look forward to detailed improvements to the well-known brake, Shimano has introduced an entirely new four-piston brake for trail and enduro riders. With the new brake levers, the clamp moves further into the middle of the lever, so that the reservoir is supported directly on the handlebars. This additional contact point is designed to increase stiffness and stability, providing an even more direct braking feel and improved control. According to Shimano, the braking power is 10 % higher than the in-house SAINT and should, therefore, leave nothing to be desired, at least concerning power.

The two-piston brake comes with a light XC lever, and the four-piston variant uses a unique SERVOWAVE brake lever with tool-free reach adjustment and adjustable free stroke. The brake pads and discs have also been reworked to provide even better heat dissipation with less weight.

Shimano XTR M9100 Hubs

Shimano has introduced hubs to match the new freehub body. The highlight of the new XTR hubs is the SCYLENCE technology, which is supposed to enable almost noiseless freehub operation. The well-known pawls have been replaced by a ratchet system to reduce frictional resistance. The HR hubs are available in 142 mm and 148 mm width with 12 mm thru axles, the VR hubs in 100 mm and 110 mm with 15 mm thru axles.

Our first impression

Shimano is back! While the old XTR has lost some of its appeal next to the SRAM Eagle, Shimano is back in the game with the M9100. We still have to be patient until we can test the XTR ourselves, but the key points already sound very promising. In addition to the broad range 1x drivetrain, trail and enduro riders can look forward to the new four-piston brake, because if Shimano’s specifications are correct, the new brake promises to be an absolute beast.

More information at shimano.com


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Words: Photos: Shimano