Shimano XTR 9100

Shimano Launches Its First 1×12 Drive: 51-Tooth XTR 9100

An industry-leading 10- to 51-tooth cassette crowns Shimano’s latest, customizable mountain bike groupset.

Shimano XTR 9100

With the front derailleur all but dead in the mountain bike world, component manufacturers now race to cram more gears in the rear. And today Shimano set the bar just a bit higher with the launch of its XTR 9100 series groupset.

The component upgrade includes everything – disc brakes, shifters, derailleurs, crankset, hubs, and more. But the crown jewel has to be Shimano’s first 1×12 drivetrain, with a massive 10- to 51-tooth cassette. And for those keeping score, that gives the Japanese brand one more tooth than SRAM’s 10- to 50-tooth XX1 Eagle cassette.

Shimano XTR 9100 SRAM XX1 EAGLE
Shimano XTR 9100 10- to 51-tooth cassette (left); SRAM XX1 Eagle 10- to 50-tooth (right)

Shimano XTR 9100: 1×12 MTB Drivetrain

According to Shimano, the new line arose out of “extensive feedback from its global mountain bike athletes.” It aims to deliver semi-customizable gruppos depending on rider preference.

Shimano XTR 9100

While the 1x system is the highlight of the XTR 9100 series, Shimano also included a double-chainring option. The 2x system offers 38/28 teeth in the front and 10–45 teeth in the rear. Both single and double setups use an M9100 Hollowtech II crankset and sport Shimano’s new “Hyperglide+” cassette design.

The brand claims the Hyperglide+ system smoothes out shifting up and down. While both Shimano and SRAM have dedicated, loyal followings, those who compare the brands’ shifting prowess will appreciate faster and smoother shifting from the Japanese manufacturer.

As for the riders who’ve embraced the 1x revolution, Shimano has more customization options. The XTR 9100 1x groupset offers three drivetrain setups: Wide Range, Rhythm Step, and Lightweight.

The Lightweight sports 11 speeds, weighs 299 grams, and runs 10–45 teeth. The Rhythm Step has the same gear range but adds a 12th gear for smoother shifts. And the big daddy Wide Range offers a huge 12-speed range, from 10 to 51.

Shimano XTR 9100 brakes
Shimano XTR 9100 Enduro brake lever (left); XC (right)

The XTR M9100 groupset also offers two-piston XC and lighter four-piston enduro hydraulic disc brake options. Check out the full line here and see all the new upgrades and setup possibilities.

Adam Ruggiero

Adam Ruggiero is the editor-in-chief of GearJunkie and a fan of virtually all sports and activities. From biking, running, and (not enough) surfing, to ball sports, camping, and cattle farming — if it's outside, it's worth doing. Adam graduated from the University of Minnesota with a BA in journalism. Likes: unique beer, dogs, stories. Like nots: neckties, escalators, manicured lawns.