Shimano XTR FC-M9120 12-Speed Crank Set

Class-leading XTR 12-speed crank set, integrating the bottom bracket and crank set into a strong, rigid, yet lightweight unit.

The Shimano XTR FC-M9120-1 crank features an entirely new construction, using direct mount chainrings, special gear tooth profile for improved chain retention, and a narrow 168mm Q-factor. The FC-M9120-1 uses a 52mm chain line and can be converted between 1x and 2x, with 30, 32, 34, 36, and 38T chainrings available. On offer are 165, 170, and 175mm crank arms.

Technology

Dynamic Chain Engagement+

Shimano’s Dynamic Chain Engagement+ is a special gear teeth profile designed for use in single-chainring configurations for XC, enduro, and trail riding.

It gives more chain retention and smoother pedaling - even over bumpy terrain. Chain retention of any gear will reduce abrasion and worn out.

HG Chain Design for HyperGlide+

HyperGlide+ dedicated chain delivers greater chain retention, improved shifting efficiency, and smoother transmission over rough terrain.

Benefits and features:

• Improved chain retention encourages more aggressive all-terrain riding and relieves chain-issue anxiety
• Smoother drivetrain transmission and enhanced shifting performance sharpens riders’ concentration and improves acceleration
• Better chain engagement cuts abrasion, reduces maintenance, and lengthens the lifespan of the chain

Revamped HG chain features an extended inner link plate that connects seamlessly with new chainring tooth shape for ultra-efficient drivetrain performance.

This design change reduces the vibrations normally caused by the inner and outer chain plates rolling onto the chainring, and provides better chain engagement, stronger retention, and smoother pedaling.

HollowTech II

Providing the best balance of stiffness, strength, weight and rotating performance.

The concept of HollowTech II technology is focused on producing a superior crankset which will maximize a rider’s power transfer. The rigidity of the crankset ensures pedaling efficiency while its weight, a key element of the crankset, you want light, aids in cycling longer distances over which the rider needs to pedal more. Naturally, Shimano strove for the optimum balance between the conflicting needs of stiffness while producing a lightweight crank. HollowTech technology is an ultra-lightweight hollow crankarm created by Shimano with the company’s own proprietary forging technology that also maintains rigidity. The addition of HollowTech II technology integrates the bottom bracket axle with the right crankarm for more stiffness and a weight savings to achieve a high-dimensional balance. Its outboard bottom bracket bearing system provides better weight distribution and more pedaling stability, allowing for more efficient power transfer.

The HollowTech II crankset has been developed by pursuing the optimum balance of stiffness & rotating performance in a lightweight and beautiful crankset design. Moreover, HollowTech II crankset has a high-precision sealing in the bearing area to increase durability maintaining the excellent rotating performance for long periods.

24mm Diameter Axle And Bearings

Why choose the 24mm axle and bearings for the HollowTech II crankset?

The diameter of the Bottom Bracket axle and bearings was of primary importance for the development because the Bottom Bracket axle area is tied to such key elements as stiffness, strength, weight and rotating performance.

What’s important is the total balance of crankset

In addition, taking the crankset as a whole, the total balance of crankarm rigidity, axle stiffness, bearing position and others is essential. Indeed, the crankset is designed by careful consideration of the total balance of those elements to prevent breakage.

Outboard Bearing

For most frames with 68mm Bottom Bracket shells, HollowTech II with 24mm axle can set the bearing position outside of the frame to provide better weight distribution and more stability.

24mm Diameter Axle And Bearings Provide Optimum Balance For The Crankset

After studying all these problems thoroughly, we made the decision to adopt the 24mm diameter axle and bearings, which have the optimum balance, for the HollowTech II crankset.

In addition, an examination of the total crankset, including the crankarm and gears, proves the optimum balance of rigidity, weight and rotating performance for the ultimate transfer of power to your bike. HollowTech II is simply the most optimized crankset design on the market.

Features

• Direct mount chainrings are lightweight and easy to replace while providing increased rigidity, can be set up as single or double
• Integrated bearing preload design is lightweight and makes installation and adjustments easier than ever
• Super-lightweight HollowTech II cold forged Duralumin crank arms - hollow design saves weight whilst increasing rigidity and durability
• Easy to use splined bottom bracket spindle connection provides a rigid and secure interface between crank and spindle
• With a 52mm chain line and a 168mm Q-factor (1x set up) ideally suited for all-mountain use in conjunction with 10-51T cassette
• crank set supplied without bottom bracket and chainrings
• Compatible with all 12-speed direct mount DCE XTR chainrings, please use SM-CRM95 chainrings
• For use with 12-speed HG+ chains only