The Sram Eagle Powertrain motor and new battery tech!

There have been rumors about a new Sram motor all year. And now, all of a sudden, the Sram Eagle Powertrain is here. Check out Robs video for all the info about motor, autoshift and so on. But if you care about battery tech, remember to read the rest of this article.

The Sram Eagle Powertrain motor​

This new motor is labeled “Powered by BROSE”, and it might very well be the Brose Magnesium S motor that has been adapted for Sram. It’s a 90 Nm motor rated at 680 W max. It weighs in at 2.9 kg.

Autoshift​

Whether it’s all new or not, the motor would have to be adapted to run the Autoshift algorithms and it would need additional hardware for connection and processing.

The Sram autoshift only works with the Sram Transmission drivetrain, and it only works with this new motor. Not having tested this myself, it appears similar to the Shimano Autoshift. The system changes gears based on cadence, and it can be over-ridden or completely turned off. These systems must be able to shift under load, and the Sram Transmission drivetrain is designed to do so.



There’s also the “Coast Shift” function that allows the drivetrain to shift gears when not pedalling. It’s a nice function that allows the Autoshift to shift to the correct gear as speed goes up or down while coasting. And as you would expect, the Sram Transmission electronic derailleur now draws power directly from the main battery.

The Sram Eagle Powertrain components​

It seems the left shifter has returned, but it hasn’t! The shifter on the right side of the handlebars is indeed a shifter, it operates the Sram AXS T-type drivetrain. Sram calls this the AXS Pod controller. The very similar looking Pod on the left side controls the motor and Autoshift settings. But there is no reason to be alarmed, it controls the AXS dropper post too, which is what we all expect from a lever/button on the left side.



“The Eagle Powertrain AXS Bridge Display” is the name of the display that mounts on the frame. It’s a waterproof, illuminated, gorillaglass protected color display. There's also the "Eagle Powertrain AXS app" that lets you tweak and personalize settings.

The batteries!​

It might just be me, but this is what had me the most excited. No, not the 720 Wh battery running 21700/5Ah cells. And no, not the 250 Wh range extender that can be mounted where the bottle cage sits. See my battery video or keep on reading.



It’s the 630 Wh battery! The battery that was supposed to sit in Robs demo bike. I guess it’s not ready yet. It’s a 3 kg battery with higher energy density cells. I’m pretty sure it’s the new LG M58T cells. A high-nickel litium-ion cell with an energy density of 285 Wh/kg. These have been rumored since early 2022, and it seems they’ve finally reached the ebike market.




Now why is this such a big deal to me? The last leap in battery technology was back in about 2015. A regular ebike battery went from 400 Wh to 500 Wh with practically no weight increase. This time we’re seeing a 16% increase in capacity, which means a 5Ah cell of the 21700 format is now 5.8Ah. Your 540 Wh battery from Orbea or YT can suddenly be built with a capacity of 630 Wh. The 360 Wh battery in many lightweight emtbs can now be built as a 420 Wh battery. Future versions of your 720 Wh battery will be 840 Wh. All this while fitting in the same battery enclosure. And weight remains the same.

Wait…​

Why does the new Sram motor come with a 720 Wh battery and not an 840 Wh? Who knows, I guess the new battery cells aren’t ready yet. And perhaps Sram can’t get as many of them as they want? The 630 Wh battery isn’t out yet, so I guess Sram went with the 720 Wh battery to have a product ready for the launch.

Which bikes get the Sram motor?​

I’m looking forward to testing a bike with this motor system. But what bikes will we get? Judging by the press images, we get a Propain and a Transition. Also, the press kit mentions Nukeproof and GasGas. Some bikes should be out this fall.

My take​

The future of battery tech is here. And so is a very interesting motorsystem. The Sram Eagle Powertrain will work with any drivetrain. But the integration of the Sram AXS Transmission drivetrain is very interesting. Now both Sram and Shimano have motors that can be combined with wireless shifting to acheive automatic shifting. These are systems designed to shift under load. In addition, the design with no dropout makes the Sram Transmission more solid in the sense that it can handle impacts better.