We tried the most affordable electronic converter from this popular American brand, which works just as well as the more expensive one.

We were eager to produce this review: the SRAM S-1000 AXS drivetrain, the lowest-end model in this North American brand’s electronic groupset that still delivers excellent performance. SRAM introduced it a season ago as an entry-level option for OEM installation on mid-range bicycles.

We’ve been testing it thoroughly, as we’ve had a bike (Amflow PR Carbon Pro) equipped with this drivetrain for several weeks now. The SRAM S-1000 AXS comes in two configurations: one features a small built-in battery to power the drivetrain, while the second configuration, designed for electric bikes, draws energy from the motor’s own battery, eliminating the need to recharge that additional battery. Obviously, we opted for the second option.

SRAM S-1000 AXS: Shared Components with More Expensive Derailers

The S-1000 AXS designation actually refers solely to the rear derailleur, which shares its structure with the GX AXS T-Type. The only visible differences are the finishes, which are less elaborate since this S-1000 model is black and features more plastic. It adopts the innovative design originally introduced in the XX AXS, the most exclusive model, where its ‘full mount’ attachment to the frame (without the need for a clamp) was its most notable feature.

This S-1000 AXS features a performance firmware that ensures optimal chain shifting through the various cassette sprockets, even when pedaling at maximum power on an electric bike. Like the best derailleurs, it has a Drag Spring Cage shock absorber to hold the chain in place under harsh conditions.

As mentioned, the derailleur is the S-1000 AXS, but the other components belong to different series: for example, the button is the well-known POD Controller, which has lower aesthetic finishes compared to the POD Ultimate Controller (the most exclusive model) but offers the same functions. Thanks to SRAM’s own app, we can configure how the two buttons function—whether one raises or lowers gears, whether we can shift down multiple gears at once, etc.

Other components: for example, the cassette used in our drivetrain is a SRAM XS-1270 with a 10-52t range, a model mid-tier in the manufacturer’s cassette lineup, featuring silver sprockets on one side and black sprockets on the other. Its weight is 565 grams. Finally, the chain: it’s a Flattop design chain, the Eagle 70.

So, how does it perform?

The truth is that we were surprised by how this transmission performs. We’ve tried other higher-end SRAM transmissions, and in use, the differences are minimal (almost none). Usually, the only difference when using transmissions of different tiers lies in the feel of the levers, but since this is the POD Controller used in other SRAM models, we didn’t notice any difference at all.

Testing this transmission change on a bike like the Amflow PR Carbon Pro was crucial in realizing that electronic transmissions are ideal for electric bikes. This bike has extremely high power (up to 1,500 W and 150 Nm), and even when we pushed the motor (and our legs) to their limits, the gear shifts worked perfectly smoothly—there were no failures at any point, no unusual noises, and no feeling that the chain might get overloaded.

On the other hand, it’s a plus that the rear derailleur is powered by the motor’s own battery, so we don’t have to worry about anything other than charging the main battery.

The button is powered by a CR2032 battery, and obviously we haven’t had to replace it yet. Checking its status is simple, as there’s an LED light on the controller that turns on when pressing the buttons: if it’s green, there’s more than 25% charge left. If it’s red, there’s between 10% and 25%, and if it’s flashing red, there’s less than 10%. We recommend carrying a spare battery with us just in case (the claimed lifespan varies greatly, between one and two years).

Conclusion

There’s nothing to criticize about this S-1000 AXS transmission. Perhaps its somewhat plain aesthetic and the fact that it’s not available for purchase would be the only downsides: still, we think it’s an excellent option for upgrading our electric bikes. SRAM’s most affordable derailleur is the GX AXS, which costs 480 euros without any discounts....

Returning to the SRAM S-1000 AXS, we can say its performance is flawless, without any kind of lag. After using it, we’ve come to the following conclusion: there’s no need to spend more money on a bike just to get a more exclusive drivetrain. It’s like everything else—subject to personal preference. Functionally speaking, this drivetrain with the most basic POD Controller and the S-1000 AXS derailer works perfectly well.