Shimano XTR 9100
Words by Chili Dog | Photos by Sterling Lorence & Chili Dog
After years of speculation, Shimano has finally answered the 12-speed call with their new XTR 9100 group. Just a couple years ago, SRAM shook up the drivetrain world with the launch of their 12-speed Eagle drivetrain. I distinctly remember thinking how absurd the pie plate sized 50 tooth cog looked in the first press release photos, but now it comes spec’d on almost every review bike we throw a leg over. That OEM dominance has elevated SRAM onto a pedestal, thanks in large part to their overwhelming slice of the MTB OEM market share. Never a company to rush something to market before it’s ready, Shimano has been carefully toiling away in the shadows, as they worked on their own 12-speed drivetrain.
The new XTR isn’t just a mild change compared to the old XTR group – it’s a complete redesign. Traditionally, Shimano has developed products and then used athlete input to fine-tune them to their final form. This time, and because XTR is a race-intended product, athletes were involved from the very beginning.
Starting at the cockpit, Shimano took a step back to rethink the ergonomics and adjustability of their shifters and brakes.
After extensive athlete surveys and studies about cockpit setup, Shimano came up with an adjustable system, which allows the shifters to both roll and slide in and out on the bar. The rider simply sets their preferred brake position sliding in or out of the bar, and can then slide the shifters on a track independently. The brake and shifter aren’t tied together as one un-adjustable group like SRAM, and you no longer have to play the game of putting your brakes inside or outside of the shifter. Shimano’s new dropper remote follows the same principals on the left side of the bar. The set up is neat, clean and offers much needed adjustment for riders like myself that have large hands.
Replaceable rubber grip pads were also added to the shifters and dropper remote to add grip in wet conditions. They’re a nice touch and go a long way in improving quick panic shifts when an unfamiliar trail suddenly takes an uphill turn. The double shift capability is also retained from the previous generation, but with updates. Instead of the equal force clicks the system had before, the new XTR requires just slightly more effort for the second shift, completely eliminating accidental double shifts in rough terrain.
Shimano also completely redesigned the brake levers. To improve rigidity, the levers now have two contact points with the bar: one at the clamp, and a separate point towards the lever itself. This change improves rigidity and lever feel under hard braking. Shimano also tuned the servo wave curve with a different ramp to improve lever feel. For those wondering, it does decrease the on/off feel that Shimano opponents nag about, but still retains the quintessential Shimano feel. Reach adjustments on the enduro-oriented BL-M9120 and BR-M9120 brakes we rode came in the familiar dial form.
Two brake options are offered within the XTR line: the Enduro brakes mentioned above, sport four pistons at the caliper and aluminum levers, and the XC oriented two piston BL-M9100 and BR-M9100 brakes with carbon levers.
Our time was spent on the Enduro brakes, which share pads with the Saint lineup. Shimano’s summary is that the new brakes combine Saint Power with XTR modulation and lever feel. Their creation was in direct response to enduro racers opting to ride Saint product. For the e-bike market, expect four piston XT.
The meat of the XTR changes are in the drivetrain itself. Once again, Shimano started at the drawing board to rethink their current design. Of course the whole reason for the redesign was to introduce a 12-speed option, but Shimano actually broke the 12-speed cassette into two variants. The first is a 10-51 tooth 12-speed Wide Range cassette that offers 510% gear range. If you’re keeping track that’s one tooth more than Eagle… take that SRAM. The second option is a 10-45 tooth 12-speed Rhythm Step that offers a 450% gear range with more even gear steps.
Despite the focus on 12-speed, Shimano’s pro enduro racers still asked for an 11-speed option to reduce derailleur cage and chain length. The 11-speed option actually uses 6 less chain links, reducing weight and chain slop in the smallest gears. A 10-45 gear spread on the 11 speed offers a 450% gear range that’s 57 grams lighter than the 12-speed, 10-51 cassette. The 11-speed XTR is compatible with both short and long cage XTR M9100 rear derailleurs.
Shimano also made significant changes to the tooth profile on all three cassettes. Downshifts into the 51-tooth cog are buttery smooth and lighting fast. To put it simply, the shift into the 51-tooth is the fastest of any pie plate sized cassette we’ve been on. Upshifts are also dramatically improved thanks to the adaptation of Shimano’s Hyperglide+.
Traditionally, the chain was only guided when shifting into the larger cogs of the cassette, but with Hypergide+ that guiding happens in both directions. The result is power going to two cogs at once during a shift, and the elimination of that “clunk” while shifting into smaller cogs. It’s something that’s especially noticeable when shifting while on the gas out of a corner.
Three different derailleur options are available. The RD-M9100-SGS derailleur is designed for the 51-tooth 12-speed cassette, the RD-M9100-GS is designed for the 45-tooth 12-speed cassette, and the RD-M9120-GS short cage for the 11-speed cassette. Cages and parallelograms shorten as the cassettes decrease in size, with the mid cage design being more than an inch shorter than the 51 tooth variant. Small changes were made to the design to improve shift quality and chain management, and the large clutch lever still remains easy to access for repairs.
Another integral part of the smooth shifting experience on the new Shimano XTR is the chain itself. Large changes to the chain profile have been made to allow for quieter pedaling and improved performance at either extreme of the 1x drivetrain. The new profile also clings to the chain ring with even more tenacity. Noise is also greatly reduced and is immediately noticeable on the trail. It’s probably safe to call it the quietest drivetrain on the market.
A major factor contributing to our silence on the trail is the aptly named Scylence ratchet hubs that use two internal springs to keep the ratchets separated until you pedal. In other words, they don’t make a sound when rolling along, and have almost no resistance. The new hub design was necessary to work with Shimano’s new freehub body standard. Yes there is now another freehub standard, called Micro Spline.
If you want to run the new XTR, you’ll need to lace up one of Shimano’s four different hubs. At this time, only a limited number of hub manufacturers have access to the Micro Spline freehub design, but that will change as time goes on.
Shimano’s new XTR cranks look familiar, but the team made several important changes to the design. First and foremost, they no longer rely on mounting bolts to secure the chain ring. Instead the system uses a lock ring and tool that ships with the cranks. There’s also no pinch bolt on the non-drive side crank arm. A threaded finger ring on the non-drive side is used to adjust BB tension and 168 or 162 millimeter Q-factors are available.
The last part of the XTR group is the human contact point for the drivetrain: the pedals. Two pedal variants are offered, the M9100 XC pedal, and the M9120 Enduro pedal. Both options grew in width from their predecessors, and have options for riders looking to fine-tune their fit options. The Enduro pedal’s increased real-estate is a welcome change that should fit better with the current crop of clipless shoes. It also offers more surface area for hard charging riders looking to distribute the loads of aggressive riding.
A few months ago, we published Shimano’s press release detailing the updated Shimano XTR lineup. We’ll let you read that piece if you need more information on the specifics and different options within the Shimano XTR lineup, but let’s just say, we’ve been counting the days until we could ride the group since then. So let’s get on with it then…the question that’s been tugging away at us since the first word of XTR 12-speed– how does it perform, and is it better than Eagle?