SRAM

XX1 Eagle AXS DUB Groupset - Boost

Spec’d for race day, and hungry for blasting through cross-country laps, SRAM’s new XX1 Eagle AXS Boost DUB Groupset hits the market ready to charge to the podium. If you follow the XC race circuits, chances are you’ve already spotted this beautiful piece of machinery on Schurter’s steed, though the tech remained quiet until now, with SRAM’s release to the public. The XX1 AXS Eagle groupset offers the lightest weight materials, long-wearing durability, and Eagle’s signature 500-percent gear range to land you with the pinnacle of performance, ready to turn your steed into the next generation of superbike.

Since SRAM had its electronic expertise dialed with Etap, the first thing we wanted to know was just how much it had in common with its roadie counterpart. Just like on Etap, you’ll have a fully wire-free setup, with no need to search for a spot to store your battery — simply bolt on your shifters, rear derailleur, and pair things together. That’s largely where the similarities end. Naturally, the shifters are all new, and because the demands on mountain bikes can be a bit more strenuous, harsh, and jarring, SRAM took a bit of what its designers already have learned about electronic shifting, and made some serious updates to handle the rough and rowdy conditions on the dirt. This includes a two-clutch system (we’ll get into this later), and a whole lot more torque. Etap spins at 50,000 RPM, but to get things dialed for the trail SRAM builds the AXS rear derailleur with enough torque to spin 80,000 RPM for booking it down steep and quick descents.

Compared to mechanical Eagle groupsets, the Eagle AXS derailleur has been contoured around the frame design a bit more. This translates to increased chain wrap, which improves both load distribution and durability, reducing wear and tear on your chain and cassette for better longevity of components. Dually, this new positioning offers a whole 10-millimeters of increased clearance over mechanical Eagle rear derailleurs. Speaking of clearance, the two-clutch system offers a whole new safety mechanism for when you just don’t have quite enough space, and your derailleur takes a knock. The first clutch is the traditional type-three that you’ll find in most SRAM MTB derailleurs, this keeps your chain in check and tensioned, the second is where things get exciting. The Overload clutch protects your geared motor by disengaging the motor all together in the event of impact, allowing the derailleur to move whichever direction it needs to in order to protect the motor against a rock or a low-hanging branch. As soon as the impact is over, the derailleur automatically reengages and shifts back to where you were, without skipping a beat. This built in protection gives you some serious peace of mind when you’re dropping big dollars on a groupset.

Up front in your cockpit you’ll find the AXS shifter, which uses a completely new profile with three buttons. First, there is a main paddle at the thumb that pivots up and down when you engage it. The shifter is programmed out of the box to shift into your harder gears when you press upward on the paddle, and into your easier gears with a press downward. In addition to the paddle, there’s a trigger shifter that can be accessed when you’re hammering up climbs to get into the perfect gear for your sprint. Both paddle and trigger can be fully programmed with SRAM’s AXS app, allowing you to switch what each button does, and customize how many shifts your derailleur can make when you hold down on the shifters. The shifter pairs with your rear derailleur using SRAM’s own wireless network, which they claim to be completely secure, preventing tampering with from anyone but you. With that said — the shifter also uses both Bluetooth and ANT+ to connect to head units and smart phones, which allows you to program it, view battery life, and see a maintenance schedule. If on race day you find many other derailleurs and shifters popping up on your AXS app, you need not worry. In order to adjust shifting with the app you must be physically holding your bike and pressing the shifters to make any changes to its programming, keeping your ride safe from tampering.

We’ve long known SRAM’s XX1 designation to allude to components that are the pinnacle of performance and finesse, and we see that come through in all of the details for this particular group. SRAM employs the XX1 derailleur that’s built for instantaneous shifts from a single touch, even while under massive chain loads, paired up with the XX1 Eagle Chain. We know, chains usually aren’t the most exciting piece of a new groupset, but we’d argue that SRAM’s Eagle chain is the biggest contributor to the ultra-smooth, quiet, and durable performance that we can find, and when paired up with the XG-1299 rainbow cassette, you’ll find a 500-percent gear range, and longer-wearing durability from X-Sync 2. In the front, the crankset may look familiar, and that’s because it is. SRAM’s XX1 Eagle DUB SL crankset holds down the fort with its ultra-light, ultra-stiff demeanor, utilizing SRAM’s DUB axle technology that simplifies the spindle-to-bottom bracket relationship.

An ever-critical question with mechanical groupsets is battery life. All day epics packed with steep climbs and rowdy descents mean a whole lot of shifting, and can be trying on a battery, but SRAM is confident that the derailleur can run for 25+ hours from a single charge. The battery is removable, so you don’t have to bring your steed into your living room to plug it in, you can simply pop the battery off of the back, and bring it in to be charged easily with a USB device. SRAM’s AXS battery remains the same from its derailleur to RockShox Reverb AXS dropper post, so if you’re sporting both on your bike you can swap the batteries around, should one run out of juice before the other. In the front, the shifter runs off of a single watch battery, and claims to have over a year of life from a single battery, keeping maintenance low.

When things get wet we can get weary of electronics, but the Eagle AXS groupset is built with seals designed to keep things working flawlessly, whether you’re booking it across a lofty stream of snow melt, or get caught in torrential downpour at the summit. With that said, much like any other components, we don’t recommend hitting it with a jet stream to wash it, as you may be able to damage the seals.

With the price difference between SRAM’s XX1 Eagle AXS and X01 Eagle AXS you’re likely wondering what the difference may be. While on SRAM’s mechanical groupset line you found a slight difference in performance between the two, on the AXS side of things you’ll find that the two derailleurs perform nearly equally. The biggest difference you will find is in weight department. SRAM’s XX1 AXS groupset is designed for total cross-country domination, and as such it shaves grams wherever possible, allowing you to power up climbs without any extra bulk, while the X01 AXS group is a bit more robust, and as such, scales in a few grams higher. Despite the addition of batteries, both the X01 and XX1 AXS groupsets scale in below the traditional mechanical Eagle groupsets.