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Free bird: SRAM Eagle AXS brings wireless shifting to mountain bikes

Redesigned shifting ergonomics and a sprint button follow from move away from cables and housing

X01 Eagle AXS

Riders have been asking when SRAM’s eTap wireless shifting road drivetrain would make it onto mountain bikes for about as long as the American manufacturer has been making it. Rumours of a wireless version of the company’s 12-speed Eagle drivetrain ramped up significantly when Olympic XCO champion Nino Schurter was spotted not-so-secretly racing with a wireless drivetrain at World Cups and 2018 world championships.

XX1 Eagle AXS

Well, the bird has finally landed. Or birds, rather. SRAM announced the simultaneous release of XX1 Eagle AXS and XO1 Eagle AXS today. Both are wireless systems, with XX1 aimed at the cross country crowd while XO1’s sturdier build aims to serve enduro racers. SRAM didn’t stop there, either. It also announced a new wireless dropper post from Rockshox, the Reverb AXS, which integrates into the system, and a 12-speed AXS version of its eTap road/cross/gravel group.

X01 Eagle AXS

The centerpieces of Eagle AXS are, of course, the wireless rear derailleurs and shifter. Without the constraint of a cable to work around, SRAM redesigned both components for the AXS system. The XX1 and XO1 wireless derailleurs have been redesigned to be motor-driven instead of cable-actuated. SRAM says the result is a system that is happy to shift under load, over rough terrain, during uphill efforts. The AXS controller, which is what SRAM is calling the electronic shifter, has a completely new look and ergonomics now that it is wireless. This includes the addition of a novel “sprint” lever that requires minimal movement of the hand to operate. All AXS powered components can be customized and monitored using the new AXS app.

SRAM Eagle AXS rear derailleur

SRAM insists the new system is more than a mechanical derailleur with a battery strapped on. The wireless version of the Eagle derailleur has been fully designed around its motor-actuated shifting. Like Red eTap on the road, Eagle sets up quickly. Pair the derailleur with the controller, attach to the bike, and trim using a small button, then go ride.

Compared with mechanical Eagle, the new wireless bird has a shorter cage, giving you an extra 10mm of ground clearance, and sits farther forward and inboard. Eagle AXS uses the same battery as the Reverb electronic dropper post and eTap road group. SRAM claims you’ll get approximately 20 hours of trail time between charges.

Eagle AXS Impact Protection

Calling the Eagle AXS derailleur the “brain” of the system, SRAM has designed a safety mechanism into the high tech part. The Overload Clutch was designed to disengage on impact, then return to position and shift back into gear. This feature protects the derailleur’s motor, as well as saving the rest of the component and the bike’s derailleur hanger in the process.

Eagle AXS controller

Instead of just removing wires, SRAM has redesigned the function and ergonomics of its wireless shifting mechanism. Touchpoints are customizable, allowing riders to choose which button does what. There are three options: Inboard shift, Outboard shift, or dropper. You can program all touchpoints using the AXS app, including integrating Rockshox’s wireless Reverb AXS dropper post.

The Eagle wireless controller runs on a single CR2032 watch battery. A power save mode preserves battery life when you’re not riding, but wakes up to a single touch. Lifespan for the battery is predicted to be in the range of two years.

X01 Eagle AXS
SRAM’s sneaky sprint button
Secret sprint paddle

One new feature opened up by the potential of wireless shifting is the new “secret” sprint paddle. This extra paddle sits on the front side of the controller, where it can be easily reached for quick shifts with minimal change to the grip on the handlebar.


Designed for the demands of World Cup XC racing, XX1 Eagle AXS combines SRAM 1x technology with the lightest-weight materials. The XX1 derailleur uses a carbon cage, titanium hardware, and a distinctive rainbow colourway. The system comes with a colourful rainbow chain to match, which uses a PVD titanium nitride coating to create its sparkle. SRAM says the rainbow chain is exclusive to the wireless system but, other than being really eye catching, does not provide any performance improvement compared with the mechanical XX1 coating.

Despite adding batteries to the system, ditching cables allows SRAM to keep wireless XX1 the same weight as mechanical XX1. The claimed weight is actually five grams lighter than the current equivalent mechanical system.


Focusing on durability over maximizing weight reductions, XO1 Eagle uses a forged aluminum derailleur cage in place of XX1’s carbon cage. Instead of the rainbow colours of XX1, XO1 comes in a black/polar colour option.

Eagle X01 AXS manages to drop approximately 15 grams in the wireless version of the system, compared with its mechanical twin.


This is where the “access” moniker comes in. SRAM’s new app lets you adjust the functionality of Eagle AXS to your personal preferences and then monitor your usage. You can go one step further and connect AXS hardware to your SRAMid, which will, among other things, send service reminders when it’s time to check your components’ wear.

The main feature of the app is to program SRAM’s wireless system according to your preferences. It lets you personalize controller assignments for shift commands, including the Reverb electronic dropper post. You can further expand Eagle’s capabilities by adding SRAM “Blips” to the system, if you choose.

X01 Eagle AXS

RELATED: SRAM joins 12-speed party with Red eTap AXS road groupset

SRAM Eagle AXS pricing and availability

XX1 version of SRAM’s Eagle AXS has an MSRP of US$2,000 for a complete groupset. This includes the XX1 rear derailleur with battery, TriggerShifter, DUB crankset, 34t X-Sync 2 direct mount chainring, rainbow chain, and the XG-1299 10-50t cassette as well as charger and b-tension chaingap gauge.

XO1 comes in at a bit less, at US$1,900 for a complete groupset. This figure includes the XO1 rear derailleur, XG-1295 10-50t cassette and XO1 crankset with 32t X-Sync 2 chainring, as well as the AXS controller, rainbow chain, charger and b-tension chaingap gauge.

SRAM says both wireless Eagle groupsets will be available to consumers in February 2019.