Electronic shifting has been on the rise for several years. The American company SRAM wants to get this technology with the SRAM Eagle GX AXS drivetrain now also in the mid-range segmet. Whether wireless shifting has an advantage over cable-driven rear derailleurs, I find out in this review.
SRAM GX AXS Group
The complexity of the bike‘s looks is altered by a missing shifter cable. The entire SRAM GX Eagle AXS groupset looks solid. The dark gray crank arms were made of aluminum, the rear derailleur has an extra plastic protective cage around the battery, and the appearance of the drivetrain should look unbreakable. The 12-speed rear derailleur was redesigned from scratch to meet the technological requirements of the AXS system. Visually, this is noticeable, among other things, that the derailleur sits flatter behind the chainstay and thus in a more protected position. In addition, the engine-protecting Overload Clutch was implemented. As soon as the derailleur takes an impact, the internal motor decouples to protect the clutch from overload. The retracted SRAM GX Eagle AXS rear derailleur returns to the original position after about one second.
What has switched via an cable now transforms into digital signals. The inner workings and optics of the AXS controller were adapted on the requirements of wireless technology. Instead of cable-pulling levers, you‘ll find a paddle that extends to the front of the controller via a pivot point. The thumb nestles the plastic surface of the paddle and audibly clicks into the next gear. The controller is easy to operate with the thumb while riding. The single front button, which can be reached with the index finger, lets you engage a heavier gear. The button assignment can be personalized using the app so that, for example, the rear derailleur shifts through the gears when a button is held down instead of selecting each gear individually. All AXS components are compatible with each other. Thus, for example, you can operate the GX AXS controller with an X01 or XX1 AXS rear derailleur.
The Eagle logo with GX lettering is set off on the slim aluminium crank. Mounted on it is an interchangeable 32 tooth chainring, whose tooth profile also allows riding without chainguide. The silver ring on the teeth is an optical feature rather than caused by the material. The back of the GX crank arms are hollowed out to save material.
Associated with the GX Eagle drivetrain is a riveted 12-speed steel cassette with a gear range of 10 to 52 teeth. The open design helps save material. Due to the largest, single aluminum chainring you can climb steep sections with a higher gear ratio.
The highlight of the SRAM GX Eagle AXS drivetrain is possibly the derailleur. On the bike, it looks chunkier than a cable-driven rear derailleur. The GX AXS should withstand high loads, especially in the Gravity range, thanks to a stable choice of materials. The large plastic rollers are held by a steel cage. Overall the unit is with about 470 grams not particularly light. On the side you will find a light emitting diode as well as an AXS button. The rear derailleur will shift by pressing the side button or it opens the wireless communication channels. The spacing of the sprockets is stored in the computer, so the gear selection should always be the same. The protective cover of the battery is not mandatory. Underneath we find a 300mAh strong battery. The battery status is communicated via the LED on the rear derailleur or displayed in the AXS app. To conserve capacity, the rear derailleur deactivates after one minute and is reactivated by movement. The battery is compatible with all AXS components and can be charged with the AXS charger.
The AXS controller can be operated well with the thumb and with a noticeable click it logs in the gear selection. The SRAM GX Eagle AXS rear derailleur changes faster than conventional derailleurs the gears. If you change several gears at the same time, the precision and speed is more noticeable. You can be sure that the next gear will sit. This can also lead to the fact that the relationship with the bike is influenced. The chain glides precisely over the cassette and the chainring and gear changes under load, for example, in steep uphill sections, are also executed with quieter chain crackling.
Fast, precise gear changes
Long battery life
Price (especially in contrast to conventional derailleurs)
Overall, I can say about the SRAM GX Eagle AXS rear derailleur that the gear change is fast and precise. I have now driven about a hundred kilometers and the rear derailleur apparently still has over 50% battery capacity. The buttons of the Controller are good to reach even while riding downhill. Overall the GX AXS groupset convinces by consistent performance.
To clarify the question of whether the SRAM GX Eagle AXS rear derailleur changes gears better I can say: Yes! However, the performance difference is minimal. Also, you have to keep in mind that you would get for the price of the rear derailleur and controller also a high-end SRAM XX1 set.