SRAM XX1 EAGLE 12-SPEED DRIVETRAIN TEST

SRAM XX1 EAGLE 12-SPEED DRIVETRAIN

More Freedom To Roam

It fits: One of our first questions with the new 12-speed gearing was if riders would have to run Boost spacing to make the cassette fit. The 50-tooth cog has a slight dish that allows for the extra gearing to fit in the rear triangle, not requiring riders to worry about new spacing standards.

Eagle has taken the cycling community by storm and shocked riders with the introduction of a massive 50-tooth rear cassette. SRAM paved the way for the single-ring drivetrain with the release of the original 1×11 XX1, which was considered massive for the time with its 10-42 cassette; however, many riders were still skeptical about the gear range of a single-ring system. SRAM responded to that skepticism with the new Eagle drivetrain.

Tech info:

The Eagle drivetrain comes in two distinct versions: the XX1, which we tested here, and the X01 version which is less expensive. The XX1 drivetrain is designed for gram-counting XC guys, while the X01 system sports the same gear range but is designed for all-mountain and enduro riders. Aside from the flashy gold coloring, the massive 50-tooth rear cog is the most eye-catching part of the group, pushing some to say that there is more cog than rear wheel. The XG-1299 cassette offers a robust 500-percent gear range that rivals most 2x systems. This cassette works in conjunction with a redesigned rear derailleur that was built with a new Type-3 roller bearing clutch and new oversized pulleys to compensate for the massive cassette.

More is more: Eagle is the first 12-speed drivetrain to hit the cycling world, and it has made an epic splash. Aside from the gold trimmings and new 10-50 cassette, the Eagle has plenty of new technologies that gave our test riders a lot to consider.

One of the biggest changes SRAM made with the XX1 Eagle is a new shifter pod with redesigned internals. The new design has a smoother feel and engagement, along with a carbon trigger to reduce over-all weight. Given that there is a substantially bigger climbing gear, there is more chain length floating around, which led to a new front chainring design to accommodate the extra material. The X-Sync 2 uses the same circumference chainring, but deepens the channels between the teeth so that they resemble a claw for better retention (hence the name Eagle). Along with the new chainring design is a redesigned set of carbon cranks that are claimed to be lighter and stiffer than the previous XX1.

It’s bold: The rear cassette offers the same gears as the previous 11-speed XX1, but with the addition of the 50-tooth cog. The rear derailleur uses a new clutch mechanism that was designed specifically for the new cassette.

On the trail:

Dialing in the shifting and the chain length was a bit different from anything else we have worked on in the past. The limit screws were as straight-forward as on any other drivetrain, but it took some finesse to dial in the B-tension screw. SRAM has guidelines to setting this, but it will take some trial and error. Some of our test riders preferred a 34-tooth front chainring on the 11-speed XX1, so for the sake of consistency, we stuck with that size for the first part of our testing.

If there wasn’t enough before: It took a few rides to remember that we had an extra gear left, but once we adapted to the new cassette we appreciated the extra gearing, especially during long days in the saddle. Riders who didn’t feel comfortable enough with a 42-tooth will have little to complain about with the bigger range.

You can’t miss it: The 50-tooth cog is tough to miss with its incredible size rivaling front chainrings used for road bikes. The application, though, is effective and will open the doors for certain riders who need that extra push to help them get up the hills.

The new shifting mechanism has a very distinct, crisp feel, with a much smoother shift than the 11-speed shifter. Through the whole cassette range the shifting had a very linear feel, even when shifting up into the 50. The question that all of our testers wanted to ask was, “How will that 50 feel?” Most of us here at MBA thought that the 42-tooth on the XX1 offered plenty of gearing, so we were curious to see how we would adjust to the new range. The first couple rides proved that our muscle memory was on point, as we simply forgot we had an extra gear when the climbs got long and extra steep. After reminding ourselves a few times that there was still a little more left on the back end, we found that the 50-tooth cog provided a solid “bail-out” gear when we were spent or if we were conquering a steeper-than-normal stretch of trail. Under heavy loads the derailleur smoothly made the jump from 42 to 50 and came down once the trail let up.

A crisp engagement: One of the first aspects we noticed with the new Eagle was the crisp shifting engagement. The shifter lever uses new internals that give the rider a linear feel throughout the gear range.

Over rougher sections of trail, the new chainring worked well to keep the chain in place. The new clutch system in the rear derailleur minimized chain slap, but we did have a couple loud hits on really rocky sections.

Hence the name: To pick up the extra chain length that is needed to fit the bigger cassette, SRAM redesigned the teeth on the front chainring. The overall circumference of the ring is the same as the previous 11-speed, but the channels between the teeth were deepened and the teeth were given a claw-like shape.

Only a couple of our test riders found that they could make the jump up to a 36-tooth chainring up front. You will be able to gain more speed on the top end with a bigger front ring, but that’s not necessarily something that every rider will need to do, as a 32 or 34 (on more technical terrain) is plenty. No matter how you see it, the Eagle will allow riders who haven’t made the jump to 1x to ride the same trails that they ride on their 2x set- ups. If you’re a little afraid to make the switch, it will only take one ride in that glory gear to see that a 1x can give you the range that you’ve been looking for.


 THERE ARE SO MANY WAYS TO GET MOUNTAIN BIKE ACTION

Mountain Bike Action is a monthly magazine devoted to all things mountain biking (yes, that’s 12 times a year because we never take a month off of mountain biking). It has been around since 1986 and we’re still having fun. Start a subscription by clicking here or calling (800) 767-0345.

Available from the Apple Newsstand for reading on your iPad, iPhone or iPod Touch.

Subscribe Here

Contact us via email at mbaction@hi-torque.com
____________________________________