Speed read: SRAM GX Eagle AXS

It’s no secret that we are fans of SRAM’s wireless AXS drivetrains. There’s just something extremely satisfying about the effortless shifts, easy installation, and clean, cable-free cockpit. Now, the refinement, simplicity, and reliability of AXS technology are available in the more affordable GX Eagle AXS trim, giving more mountain bikers the opportunity to experience the benefits of wireless shifting.

GX Eagle AXS key features:

• The electric motor allows the derailleur to shift on command, even under load.
• The fully wireless design means no cables, housing, or wires to manage.
• The Overload clutch protects the derailleur from impacts.
• A new lightweight battery cover protects the battery.
• It’s compatible with all other Eagle components including the new expanded-range 10-52T cassette.
• AXS software allows users to customize shift options.
• The system is completely waterproof and dustproof to IP69K.

GX Eagle AXS weight:

• Rear derailleur: 468-478g
• Shifter/controller: 70-82g

GX Eagle AXS pricing:

• Upgrade kit: $600
• Rear derailleur (battery not included): $370
• Shifter/controller: $150
• Battery cover: $20

GX Eagle AXS components and upgrade kit

New for 2021, GX Eagle AXS combines SRAM’s proven AXS technology with the durability and affordability of GX. The two new additions to the GX line-up are the wireless GX Eagle AXS rear derailleur and a MatchMaker X compatible wireless controller. Both are compatible with any other components in the AXS ecosystem and all Eagle cassettes, crank arms, chainrings, and chains. This allows riders to easily mix and match any Eagle components to suit their needs. The GX AXS derailleur and controller are finished in the same black and gray colorway as GX mechanical and the battery is the same battery currently used on all AXS derailleurs.

A nifty addition to the GX Eagle AXS rear derailleur is the new battery cover, a lightweight cowling designed to protect the battery from impacts and trail debris. This cover was teased in the 2019 launch of XX1/X01 Eagle AXS but has not been available until now. The AXS battery cover can be purchased separately and fits all AXS mountain bike derailleurs. The battery and electronics are waterproof and dustproof so they can survive power washing and continue performing, no matter the riding conditions.

GX Eagle AXS components can also be purchased as an upgrade kit. The upgrade kit includes the rear derailleur, controller, battery, charger, and chain-gap tool. The kit makes it easy for riders to swap their current mechanical Eagle drivetrain to wireless without buying an entire group.

As with all AXS drivetrains, installation is incredibly easy. Bolt the derailleur on. Set the limit screws and B-gap. Install the controller on your handlebars. Connect the chain. Press the pairing buttons. And go. The rear derailleur trims and adjusts itself electronically for a perfect chainline so you can set and forget. You can also micro-adjust the rear derailleur if needed. If you want to tinker, there is a free companion app (iOS and Android) that allows you to customize the shift button functions.

GX Eagle AXS vs. XX1/X01 Eagle AXS

Similar to SRAM’s mechanical drivetrain, GX Eagle AXS uses less-expensive materials to reduce cost, compared to the higher-end XX1 and X01 offerings. For example, the rear derailleur uses a steel pulley cage, steel bearings, and steel hardware as opposed to the carbon cage, ceramic bearings, and titanium hardware found on the top-of-the-line XX1 derailleur. Reduced machining and less-refined finishes (XX1 components come in flashy gold and oil-slick colorways) also contribute to lower cost.

The chart below covers the differences in price and weight between GX AXS, X01 AXS, and XX1 AXS components:

Beyond appearance and price, the biggest difference between GX Eagle AXS and XX1/X01 AXS is additional weight in the rear derailleur, 100-128 grams. This is about a quarter of a pound, and the average rider likely won’t notice the difference. All derailleurs use the same battery which weighs 20 grams. If you’re interested in examining the differences in price and weight for other components like cranks and cassettes, check out our detailed comparison of mechanical GX Eagle vs. XX1 Eagle.

Overload clutch

Riders who abuse their equipment won’t have to worry about the durability of the GX Eagle AXS rear derailleur as it benefits from the same Overload clutch technology used on XX1 and X01 AXS rear derailleurs. Like GX mechanical, there is still a Type 3 roller bearing clutch to control cage movement and prevent dropped chains. But the addition of the Overload gearbox clutch protects both the derailleur and the wireless motor in the event of an impact.

Overload is essentially a tiny electric motor spinning at 80,000 RPM paired with a gearbox. In the event of an impact, the motor’s gearbox disengages, giving the derailleur freedom to move and absorb the impact. It can then reengage and return the derailleur to its original position. The derailleur will realign itself in a split second, creating a seamless experience for the rider.

Primarily, the Overload Clutch protects the derailleur's shift motor, but it also protects the derailleur itself and the derailleur hanger from rock strikes, crashes, or your bike tipping over.

Who’s it for?

The industry has essentially declared that electronic drivetrains are the future of cycling and SRAM AXS is at the forefront. AXS is also the only current option for riders who want a 12-speed electronic drivetrain as Shimano has yet to release Di2 versions of its current 12-speed offerings. AXS drivetrains are ideal for riders who don’t want to deal with the hassle of installing and maintaining cables, or who need consistent shift performance in tough riding conditions with lots of mud or dust.

Each SRAM group also has a clear target audience. XX1 AXS offers maximum bling and minimum weight for top-of-line XC and trail bikes. X01 AXS is less flashy but keeps the performance of XX1 to suit riders looking for something more understated. And now, GX AXS is the most approachable wireless group. It gives tech-savvy, budget-minded riders an entry-point to experience all the benefits of electronic wireless shifting.

The overall weight gains over XX1 and X01 aren’t dramatic, so only the most obsessive weight-weenies should be concerned, and the attractive price is, of course, the biggest benefit. Expect GX Eagle AXS to revolutionize the entry- to mid-level bike market, as most riders who try AXS will have a tough time going back.