New Shimano DEORE XT & SLX groupsets bring 12-speed features to MTBs

Shimano has brought 12-speed to its DEORE XT and SLX groupsets, based off the experiences of some of the world’s best mountain bike racers.

The new DEORE XT M8100 series, the latest iteration of the original MTB groupset, continues its legacy with high performance features for MTB, and will be available from mid-June 2019.

The SLX M7100 series, molded from the same DNA as XTR and DEORE XT, has been designed to deliver quality performance for those exploring their MTB calling, available from July 2019.

Henry Bosch, Shimano Europe MTB Product Coordinator, said: “Whilst speed, focus and control was the mantra we lived by during the XTR development, we needed to widen that for DEORE XT and SLX. We thought a lot about how and why people ride mountain bikes.

“For us that answer was in making a set of components in the right grade and specification to match the competitive ambitions, the adventurous riding styles and the performance quality of mountain bikers across the globe, above all making sure that riders receive durable performance to have as much fun as possible.”

The new DEORE XT M8100 series is designed to provide high performance features for today’s demanding and adventurous mountain bikers, whereas the SLX M7100 series, sharing the same DNA, draws on this inspiration to bring quality performance to those discovering the fun of mountain biking…



The new DEORE XT M8100 series includes a number of ramped up features, such as:

  • Shimano’s 12-speed Micro Spline cassette sprockets with either a 10-45T or 10-51T range
  • 1×12 or 2×12 Hollowtech II cranksets
  • Powerful 2-piston or 4-piston brakes
  • Fully-adjustable ISPEC-EV shifters
  • 12-speed precision-shifting front and rear derailleurs
  • Rapidly cooling ICE Technologies Freeza rotors
  • Complete XC or Enduro wheelsets


The DEORE XT 1×12 crankset features Hollowtech II crank arms with an integrated bottom brack axle and hollow crank arm, while chainrings come with a Dynamic Chain Engagement+ tooth profile to improve chain retention, smoothness and quietness of the drivetrain.


The crankset comes with 28T, 30T, 32T, 34T and 36T chainring options, interchangeable with XTR and SLX rings, has crank length options of 165mm, 170mm, 175mm and  180mm.

Crankset weights: FC-M8100-1: 620g, FC-M8120-1: 628g, FC-M8130-1: 636g (All 32T; 175mm, w/o BB)


DEORE XT 12-speed cassettes come with the Micro Spline fitting system and are available in a 10-45T option for small gear steps or a 10-51T option for maximum range. Both cassettes also feature Hyperglide+, allowing for quick up and downshifts and an extremely quiet drivetrain.

The cassettes have an aluminium spider to house ten steel sprockets and two aluminium sprockets for optimum durability and weight.

Weights: 470g and the 10-45T option weighs 461g.


Weighing 252 g, the new 12-speed HG chain has been redesigned with an extended inner plate to improve chain engagement and retention and comes with chromised roller link plates for enhanced durability and smoother and faster shifting both up and down the cassette.


Coming in either single (RD-M8100-SGS) or double (RD-M8120-SGS) chainring variants, the DEORE XT rear derailleur enables precise and quick shifting over a wide gear range. Both derailleurs feature Shimano Shadow RD+ positioning, bump stoppers and 13T pulley wheels to make rides quieter and more enjoyable.

Rear derailleurs weights: RD-M8100-SGS: 284g, RD-M8120-SGS: 290g.

The front derailleur comes in one specification for both 48.8mm and 51.8mm chain lines but is available for D-type, E-type or M-type mountings.

Front derailleur weights: FD-M8100-D: 135g, FD-M8100-E: 106g, FD-M8100-M: 114g.


The ISPEC-EV shifters feature side adjustment and rotational adjustment options, rubber padding on the paddles and a two-way release to enhance shifting. The right hand shifter (SL-M8100-IR) uses a multi-release feature to quickly dump cassette gears and, for riders using a 2×12 set-up, a MONO lever on the left (SL-M8100-IL) shifts the front derailleur both up and down with precision. Deore XT M8100 shifters are also available in a clamp band version.

Shifter weights: SL-M8100-IR: 120g, SL-M8100-IL: 73g, SL-M8100-R: 117g, SL-M8100-L: 78g.


DEORE XT brakes calipers are available in an XC-specific 2-piston version or a Trail/Enduro 4-piston version. The 2-piston version shares the same design as the previous XT M8000 version, which means the previous G02A/3A/J02A/3A resin brake pads or G04S/J04C metal pads are compatible, whereas the 4-piston version is a completely new construction drawn from the XTR M9100 design.

The brake levers work with both the XC and Trail/Enduro calipers and come equipped with Shimano’s Servo Wave system and are now angled in two positions against the handlebar for a stiffer brake sensation. The levers also feature a reach adjust dial and a free stroke adjustment screw for simple brake tune-ups on the trail.


The redesigned DEORE XT-level ICE Technologies Freeza rotors are designed to maximise cooling, resulting in consistent brake performance and longer lasting brake pads. A sandwiched aluminium core, fused in a durable steel outer layer, dissipates heat via the heat fins in the centre.

Sizes available are 140mm (88g), 160mm (109g), 180mm (132g) and 203mm (164g).


the Shimano DEORE XT M8100 series offers complete 27.5″ and 29″ wheels for XC and Trail/Enduro riding. The XC wheels offer a 24mm wide tubeless ready, fully closed rim bed for tyres up to 2.35″.

Both the XC and Trail/Enduro rear wheels feature E-THRU axles (15mm front, 12mm rear), 148mm O.L.D. widths and come with Shimano’s Micro Spline cassette interface on the rear hubs.

Hub weights: HB-M8110: 142g, HB-M8110-B: 147g, HB-M8110-BS: 158g, FH-M8110: 305g, FH-M8110-B: 307g, FH-M8110-BS: 306g, FH-M8130-B: 310g.


The new SLX M7100 series is designed to bring premium technologies to those discovering mountain biking through:

  • Shimano’s 12-speed Micro Spline cassette with either a 10-45T or 10-51T range
  • 1×12 or 2×12 cranksets
  • Dedicated SLX-level-12-speed chain
  • 2-piston or 4-piston brakes
  • Fully adjustable ISPEC-EV shifters
  • Optimised front and rear derailleurs
  • 12-speed ready hubsets


See DEORE XT crankset description.

Comes with 30T, 32T and 34T chainring options, interchangeable with XTR and DEORE XT rings, and has crank length options of 165 mm, 170 mm and 175 mm.

Weight for the FC-M7120-B2 (36-26T, 175mm, w/o BB) is 682g and for the FC-M7100-2 (36-26T, 175mm, w/o BB) is 674g.


See DEORE XT cassette description.

The CS-M7100-12 10-51T cassette weighs 534g and the 10-45T option weighs 513g


The SLX new 12-speed HG chain has been redesigned with an extended inner plate to improve chain engagement and retention and comes with SIL-TEC roller link plates for smoother running and more durability in all conditions. The CN-M7100 chain (113 links + Quick Link) weighs 252g.


See DEORE XT derailleurs description.

Rear derailleurs weights: RD-M7100-SGS: 316g, RD-M7120-SGS: 322g.

Front derailleur weights: FD-M7100-D: 135g, FD-M7100-E: 166g, FD-M7100-M: 114g.


See DEORE XT shifters description

Shifter weights: SL-M7100-IR: 121g, SL-M7100-IL: 73g.


See DEORE XT brakes description

XC style brake kits with rotors and brake pads weigh 425g and the Enduro style brake kits weigh 444g including rotors and pads.


The SLX-level ICE Technologies rotors are designed to cool rapidly thanks to a sandwiched aluminium core, fused in a durable steel outer layer, resulting in consistent brake performance and longer lasting brake pads. Sizes available are 140mm (121g), 160mm (133g), 180mm (159g) and 203mm (193g).


Individual SLX front hubs and rear Freehubs are available in widths of 100mm and 142mm, 110mm and 148mm, or 157mm. The Freehub features a cassette body with Shimano’s Micro Spline design.

Hub weights: HB-M7110: 142g, HB-M7110-B: 147g, FH-M7110: 350g, FH-M7110-B: 354g, FH-M7130-B: 359g.


Shimano DEORE XT will be available on bikes in June and as after-market components from selected priority retailers on Friday 14th June this year. SLX components will be available from mid-July.

Hayley Everett

Multimedia Reporter

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