Shimano’s New XT M8100 12-Speed Groupset – First Impressions

The unmistakable loamy trails of the Pacific North West.

Is 365g worth $1400 to you?

Because when it comes to features, there is very, very little to separate the new XT and XTR groupsets other than weight and dollars: XT 2301g / $1499, XTR 1936g / $2899.

We’re sure plenty of people will have no problem justifying the extra expense, whether it be in a quest to save those extra grams or just succumbing to the allure of XTR. But for the rest of us, the new XT is a rock-solid option. After riding the new groupset in Bellingham, Washington for a few days, here are our initial thoughts.

With the same Terminator-esque angular look as XTR, the new XT mech was unflappable.

12-speeds, who needs it?

We didn’t need a whopping 12-speed cassette either until we tried it. The big news with XT is the bigness of the cassette. Like XTR, it’s now available in a 10-51 tooth spread. Spanning such a huge range really requires 12 gears to make the leaps between cogs manageable bites.

There’s a lot of people who think that the shift to a huge 51-tooth low gear should be offset with a bigger chainring, but we don’t buy it. Once you’ve got lower gears, you’ll use them – being able to spin instead of mashing saves your legs and lungs. Plus, at the other end of the cassette, the move to a 10-tooth cog gives you an extra 10% top end speed over earlier Shimano cassettes anyhow.

Our test bike, a Transition Smuggler, was dressed with an XT 1×12 drivetrain and four-piston brakes.

Our XT-equipped Transition Smuggler had a 32-tooth chainring and not once did we wish to go bigger. If you are looking for other options, you can get 28 – 38-tooth direct-mount rings (the latter being an XTR ring, but it’s compatible with XT and SLX cranks as well).

If you’re still running a double chainring, shame on you. But Shimano do offer XT in a 2×12 format as well, with a 10-45 cassette for closer gear ratios. In a surprising choice of resource allocation, they’ve even developed a new left-hand shifter too, called the Mono Lever, that has just the one paddle.

We’ve also been testing out the new XTR 12-speed groupset too!

Here are 10 thoughts after 10 rides on XTR.

There’s a lot of steep climbing around Bellingham, and we made plenty of use of the 51-tooth low gear.

Shifting under power.

The refinement of the new cassette and chain tends to be overshadowed by the sheer size of the gear range, but what Shimano have managed here in ensuring smooth power delivery is probably an even more impressive achievement. Still, that’s typical Shimano – they’re continually working to refine the less glamorous but vital elements of how a product performs, rather than focusing on flashy and fundamental changes.

It’s a small touch, but a good one. The rubberised shifter paddles are beautiful and tactile, especially in the damp.

In a nutshell, you can mostly ignore the old mantra about not shifting under load with the new XT and XTR. The revisions to the shape of the inner chain plates, plus having shifting ramps in both directions on the cassette (upshift as well as downshifts) ensures the chain slides across from cog to cog like mercury, Having ridden the 11-speed XT for many years now, it’s an entirely different level of smoothness, especially when you’re jamming shifts mid-way up a climb or stomping out of a corner.

At the chainring end, there has been a revision to the tooth profile as well for better security. We didn’t experience a dropped chain in three days of hard riding on blind trails, without running a chain guide.

Tasmanian gorillas in the mist.

Ergonomically sorted.

Like XTR, the XT grouppo gets a new shifter/brake mount system, called I-Spec EV. The change to a new system will no doubt frustrate some riders who were hoping to use their existing brakes with a new 12-speed drivetrain. But at least the new I-Spec EV system is far more adjustable than in years past. With 15mm of lateral adjustment and 45-degrees rotational adjustment, you can get the cockpit sorted for your thumbs. We really loved the rubberised pads on the shifter paddles too, especially when the weather turned damp during our test rides. Our dropper post was also configured with Shimano’s new dropper lever, which matches the placement of your shifter paddle perfectly.

The new dropper lever is brilliant! It matches the position of the right-hand shifter perfectly, so there’s no stretching your thumb for the lever.
Stay cool, everybody, this is a robbery: finned pads, super chilly discs.

The brakes just keep getting better.

Our bike was equipped with four-piston brakes, which have an identical calliper shape to XTR, including the in-board hose routing which makes them look a lot neater on the bike. There are still two-piston brakes available as well, but given there’s just an 18g weight penalty to go to a four-piston calliper and a 22% power increase, we’d say four-piston is the way forward.

Also, XT equipped. Bellingham has such a cool cycling culture.

Yes, it uses the new Micro Spline freehub standard. So what?

A lot of teeth gnashing happened when Shimano first revealed their new Micro Spline freehub standard with XTR last year. Have you heard anyone whine about it since? No, neither have we. Because the world keeps turning, and so does your freehub, it’s not an item you give a second thought to once you’re riding.

XT hubs are now available in 157mm Super Boost spacing too.

There are new wheels too, but we didn’t get a chance to ride them.

XTR didn’t get a dedicated new wheel when it was launched, but XT does. This is a good thing, as XT wheels have long been a favourite of ours for their mix of durability, strength and price (even if they’ve traditionally been a bit porky). The big news here is that Shimano has finally produced these wheels with a decently wide rim, at 30mm internal, as well as a narrower 25mm version. Better late than never!

We’re going to make a point of getting the new XT M8100 grouppo onto a long-term test bike soon, to see how it stacks up against XTR over a longer period. Stay tuned!


It appears you're using an old version of Internet Explorer which is no longer supported, for safer and optimum browsing experience please upgrade your browser.