New Shimano XTR M9100 – Options, options, options

Everyone knew a new XTR group was coming, but what Shimano released today is still unexpected.

The new 12-speed 10-51 cassette wasn’t that hard to guess, but three cassette choices are unexpected. There are new hubs and brakes as well, but let’s tackle the drivetrain first.

(Full disclosure: this is all info from Shimano’s press release, we have zero time riding or even seeing this new stuff in person.)


There are three new cassettes, a new crank with double and single-ring options, three rear derailleurs, a front derailleur or ten, a couple of shifters and a new chain. Obviously, Shimano is taking the “more options, more better” route versus SRAM’s one cassette range to rule them all approach.

The options:

1. 1×12 drivetrain with 10-51T cassette
2. 1×12 drivetrain with 10-45T cassette
3. 2×12 drivetrain with 10-45T cassette
4. 1×11 drivetrain with 10-45T cassette

The double crankset isn’t a huge surprise, but the “lightweight” 1×11 option certainly is. All these drivetrain options are certainly different from SRAM’s one-cassette-for-all approach. And for those keeping track, 51 teeth is one more than SRAM’s 50. Maybe Shimano has a good engineering reason for this. Or maybe it is just an attempt to feed into the bigger-is-better approach to cassettes these days. Is it better, or does it just go to 11? We’ll find out soon enough.


Wide range: 10-12-14-16-18-21-24-28-33-39-45-51T

Rhythm step: 10-12-14-16-18-21-24-28-32-36-40-45T

Lightweight: 10-12-14-16-18-21-24-28-33-39-45T

The 11-speed cassette is the same tooth count as the 12-speed 10-51 without the largest cog. This means the spacing remains the same as the 12-speed cassettes and will work with the same shifters and derailleurs. There is a switch on the shifter to swap between 11- and 12-speed. On all 12-speed cassettes the largest three cogs are aluminum and the remainder are steel. The 11-speed cassette has two aluminum cog and nine steelies.

The 10-tooth cog requires a new cassette body. It looks like Shimano took this opportunity to change everything, resulting in the new Micro Spline cassette body.

The cassette body is now aluminum, replacing the steel or Ti options of previous hubs. The smaller and more numerous splines are designed to distribute force more evenly over a greater area, preventing the cassette from eating into the soft metal. Shimano also claims 7.5-degrees of engagement and a silent coasting which they are calling Scylence, or in the press release “SCYLENCE.” Nothing like yelling about how quiet these hubs are…..

Shimano hubs have been falling out of favor over the last decade, but if they can deliver on a silent ride and tight engagement, I can see them quickly becoming favorites once again. DT Swiss will have Micro Spline cassette bodies ready to launch when the new XTR hits the market.

The new cassette body is attached to all new hubs, in both J-bend and straight-pull options. From the press release: “SHIMANO offers a variety of hub options with the MICRO SPLINE, SCYLENCE, and CENTER LOCK technology including XTR-level M9110 and M9110-B hubs with a straight pull option (M9110-BS) as well as a more affordable non-series hub option (MT900-B) that will include a straight pull option as well (MT900-BS).”  Added to this confusing mess is a wide-flange hub the only works with the 11-speed Lightweight cassette. The hub claims to be lighter and has better spoke bracing angles.


Shimano is sticking with aluminum for its cranks, leaving carbon for other brands to play around with. The new crank is hollow forged, and in a move that shocks exactly zero people, Shimano claims the new cranks are LIGHTER AND STIFFER.

Shimano dumped the spider for the now-ubiquitous direct-mount chainring in a 30, 32, 34, 36 or 38T. Or get your double on in a single 28-38 option.

There are also two Q-factors (162 mm or 168 mm), but all cranks now use a 52 mm chainline for both 142 or 148 rear hubs. Shimano says this is “due to inner chain link plate design.” “The new design reduces natural vibrations normally caused by the inner and outer chain plates rolling onto the chainring and provides better chain engagement, stronger retention, and smoother pedaling. ” It isn’t clear how this makes a wider chainline work with a narrower hub.


There is the typical talk about the shifters be more ergonomic and how the bar looks so clean with clamps shared between the brake and shifter, etc.. Oddly enough, the left/front shift has only a single lever for upshifts and downshifts. There is also a stand-alone dropper remote. Interesting to see Shimano release this without a dropper to accompany it. Someone is paying attention there, because the cable is clamped at the lever, as it should be.


Shimano didn’t keep it simple with derailleurs either. There of three different choices:


RD-M9100-GS for single rings and 10-45 cassettes (11 or 12 speed)
RD-M910-SGS for 2×12 drivetrains (28/38 with 10-45 12-speed cassette)
RD-M9100-SGS for single-ring drivetrains with any cassette, but the only one with the range to work with the 10-51

There is also a cool little chain guide and a new front derailleur. From the press release “Continuing the company’s dominance in front derailleur technology and performance, XTR M9100 delivers the newly designed FD-M9100-D/E/M side swing front derailleur…” While I can’t argue that Shimano isn’t the dominant player in front derailleurs for mountain bikes, it also has zero real competition at this point. SRAM isn’t developing mountain bike front derailleurs and the newer players aren’t bothering with anything but 1x drivetrains. The new sideswing front derailleur probably works really, really well, but at this point, even front-derailleur-compatibility hold-outs like Pivot are giving up designing around anything but a single ring, does anyone care?

I suppose Shimano is to front derailleurs as SRAM is to Grip Shift.



The big news is the clamp moving inboard. Not sure if that will help with the persistent inconsistent bite point that Shimano can’t seem to shake, but there are claims of 10% more rigidity. The brakes are now marketed as XC or Enduro, no more Trail designation.



Other than the more rigid mounting, Shimano didn’t have much to say about other changes. Of course, the mounting is claimed to improve control, etc. Although handlebars continue to get wider, and I’ve never had an issue with running brakes and shifters and dropper levers on separate clamps, the press release says: “The new design minimizes impact on cockpit real estate, creating space between the clamp and support point for mounting other handlebar accessories.” Are handlebars in a real estate bubble that is about to burst? Will we all be riding sub-700-mm bars soon and Shimano is just getting ready? 


The big news here is the return of the four-piston caliper to XTR. Shimano claims power at the same level as its Saint DH brakes, but with more modulation. Saint brake pads fit, as do the new finned XTR pads.

Rotors are new as well, with the 140 and 160 mm rotors focusing on light weight, and the 180 and 203 mm rotor focusing on cooling.


Both XC and Trail pedals are all new. The XC pedals claim better mud shedding, a wider platform and two spindle lengths. The Trail pedals also have a wider platform but also extend that support to the back of the pedal.

 Price, Weight and Availability

SHIMANO M9100 XTR MSRP Individual Weight
RT-MT900 Qty. 2 – ROTOR 203MM/180MM $169.98 149g / 143g
RT-MT900 Qty. 2 – ROTOR 160MM/140MM $159.98 108g / 90g
SL-M9100-I SHIFT LEVER – Direct Attach – Left/Right $129.99 74g (L.), 117g (R.)
SL-M9100 SHIFT LEVER – Left/Right $129.99 79g (L.), 121g (R.)
RD-M9100 REAR DERAILLEUR GS/SGS/M9120-SGS $259.99 237g / 240 g / 241 g
FC-M9100-1/9120-1 CRANKSET – Single Front Chainring $419.99
FC-M9100-2/9120-2 CRANKSET – Double Front Chainring $589.99
CS-M9100-12 12-SPEED CASSETTE 10-45 AND 10-51 $379.99 367g (10-51)
CS-M9110 11-SPEED CASSETTE 10-45 $324.99 310g
SM-CRM95 CHAINRING (30T, 32T, 34T, 36T 38T) $129.99
CN-M9100 CHAIN $64.99
FH-M9110/B XTR FREEHUB – Boost and non-boost $329.99 231g / 231g
FH-M9110-BS XTR FREEHUB – Straight Pull $339.99 235g
FH-M9125-B XTR FREEHUB – Wide Flange $329.99 228g
HB-M9110/B XTR FRONT HUB $179.99 134g / 138g
HB-M9110-BS XTR FRONT HUB – Straight Pull $189.99 151g
FH-MT900-B Non-XTR FREEHUB $184.99
FH-MT900-BS Non-XTR FREEHUB – Straight Pull $199.99
HB-MT900-B Non-XTR FRONT HUB $67.99
HB-MT900-BS Non-XTR FRONT HUB – Straight Pull $79.99
PD-M9100 XC SPD PEDALS $179.99


The pricing is very much in line with SRAM’s X01 Eagle drivetrain, with cassette, crank, chain, shifter and rear derailleur coming in right around $1,250. I don’t have the time to compare things weight-wise, but I imagine XTR will be either similar or less than X01.

The bad news? You are going to have to wait until Fall 2018, although I suspect we’ll see this stuff show up on new bikes sooner than that.

It’s been obvious that SRAM has been grabbing market share from Shimano at the high end of the market. Instead of copying SRAM’s simple approach to a single drivetrain for all bikes, Shimano continues to offer a huge range of options. The question is: do riders want options or do they want one choice that does a fine job almost everywhere? This new XTR is trying to be a lot of things to a lot of different riders, and the geeks among us will love the details I didn’t have the time to write about. With the unexpected resurgence of XC bike this year, that gram saving 11-speed cassette might be more popular than I ever would have expected.

We have a trip scheduled in a few weeks to ride these new parts in Colorado, so stay tuned for ride impressions.


Also, where on earth are the batteries and wires and buttons and displays? Where you at, Di2? Not that I really miss you….