While XTR gets a lot of us excited, it's Shimano's XT that makes a lot more sense when you do the cost to performance calculation. The Japanese giant released their 12-speed XT M8100 drivetrain
a few months ago, and they've also reworked their XT brake for 2019, with both two- and four-piston offerings operated by the same lever and master cylinder assembly.
It's the all-mountain and trail-focused four-piston stopper with a $209.99 USD price tag that's reviewed here, and I also put it up against its main rival, SRAM's G2 RSC.
XT M8120 4-Piston Brake Details
• Intended use: all-mountain / trail
• Four-piston caliper
• Adjustable reach, free stroke
• Servowave actuation
• Mineral oil
• Weight: 301-grams (front, w/o rotor)
• MSRP: $209.99 USD (lever/ caliper) $52.99 USD (rotor)
• More info: www.shimano.com
The new four-piston XT caliper is much sleeker than the previous version.The Details
Shimano has had a four-piston brake in their XT lineup for a while now, and the calipers are using ceramic pistons that are home to the same finned, metallic pads. The updates are cosmetic and external down at this end, with a new finish, smooth edges, and inboard banjo routing that gives it a sleeker appearance. In fact, it almost looks XTR-ish at first glance, which wasn't by accident.
No big news with the calipers, then, but there are some notable changes up top. Shimano has completely redesigned the perch, with a hinged clamp that also grabs the shifter and a flex-busting outboard support that butts up against your handlebar. First used on XTR, the idea is to make the whole assembly stiffer so that the brake levers feel firmer when you're really squeezing 'em.
The lever's shaped has been tweaked a bit as well; it's now a bit taller and a bit flatter.
You'll still find the Servowave linkage (pictured to the right) hidden behind the lever blade, though. Here's the idea, according to Shimano: ''When you pull a Servowave brake lever, initial pad travel is fast, so little lever movement is needed to bring the pads into contact with the rotor. The power multiplication factor then increases rapidly at the pad-to-rim contact so more of the lever stroke is used to apply greater braking power with improved control.''
On top of that, Servowave is probably the most polarizing feature of Shimano's brakes (despite often not being mentioned at all) because of the lever feel it provides - more effort is required initially before it tapers off later in the lever's throw.
The Freeza rotors (left) are Centerlock-only, and I used their six-bolt rotors instead.
XT also gets Shimano's $52.99 USD Freeza Centerlock-only rotors, previously only seen on the pricier XTR brakes. Heat is a brake's worst enemy, and the rotor uses an aluminum core that's sandwiched between two pieces of stainless steel, with the core also extending down below the brake track to help it cool off. The only thing missing that you'll find on the XTR rotor is the fancy heat-dissipating black paint that's probably not noticeable anyway.
I tested these XT brakes on a bike that used six-bolt hubs, so I ended up with conventional rotors instead.
The hinged clamp is I-Spec compatible, and an extension butts up against the handlebar to brace the outboard end of the perch.
When it comes to adjustments, the same relatively large plastic dial can be found on the lever to change the reach, and Shimano is still insisting that the small Phillips screw alters the amount of free stroke. If you've ever turned this screw on their previous brakes, you probably already know that it does diddly squat; maybe it's functioning on the new XT brake, though...?
It's also worth noting that the SLX brake (minus the rotor) is essentially identical to XT, plus 11-grams and minus the non-functioning free stroke screw and some finishing details - it retails for $174.99 USD. Just sayin'. How'd They Perform?
If you've used Shimano's brakes in the past, and especially if you've been able to compare them to other offerings, you already know the gist of it: Plenty of power that starts with a relatively firm grab, and that power doesn't go anywhere, either.
It's the same story with the new XT stoppers, too. The initial grab will still feel a bit acute to some, especially if traction is iffy, but those who love that leave-no-doubt first grab will also love that about the new XTs. Rider weight and terrain play a part in that sort of feedback, though, and lighter riders like myself might benefit from down-sizing the rear rotor, if not both.
All the power and none of the fade - the XT brakes have enough bite for anyone.
The first few millimeters of free lever travel is slightly stiffer before the pads hit the rotor and the Servowave changes the leverage, at which point the lever is slightly easier to pull. This is all squeezed into the first half of the brake lever's travel, and not something you're thinking about on the trail. The advantage, according to Shimano, is how the ''...power multiplication factor then increases rapidly at the pad-to-rim contact so more of the lever stroke is used to apply greater braking power with improved control.
'' It's also a big factor in giving Shimano's brakes their, er, Shimano-y feel.
In fact, I've seen some high-profile Shimano-sponsored racers running the non-Servowave XTR lever (combined with a four-piston caliper) because it feels more traditional.
With four pistons and Shimano's name on them, you know these things are powerful. Those trails that are just the right combination of steep, fast, and rough to have you eventually looking for a reason to take a breather? Yeah, you're not going to be able to blame your new XT brakes as they refused to fade during my time on them.
I'll tell you what did change, though: The free stroke. It wasn't the wildly varying bite point of those troublesome Shimano brakes of a few years ago, but it would slowly move in towards the grip over a few thousand feet of descending. And yes, I'm completely aware of the irony of me moaning about the non-existent ''free stroke adjustment" earlier on only to have the free stroke change on its own during use.
Despite the free stroke increasing by roughly 50-percent during long descents, power was completely unaffected. So yeah, I could still do skids at the end of my runs, but I just had to pull the lever a lot farther.
Attention Shimano: An adjustable bite point, adjustable free stroke, or whatever else you want to call it, is needed on your high-end brakes. Sure, you can change the free stroke by advancing the pistons, but I want to be able to easily make my brakes feel exactly how I want them, not how you guys think they should feel. I suspect that you're not listening, though, as everyone else has been saying that for years now.
The new lever blade (left) is a bit taller and flatter, but it felt the same to me. Shimano's brakes all have this silly release button (right) that you need to depress to open the clamp. It's a pain in the ass to deal with.
All the power+
Firm lever feel
Bite point worked its way in-
Free stroke isn't actually adjustable