FIRST RIDE REPORT

SRAM EAGLE eMTB POWERTRAIN

Words by Robert Johnston | Video by Max Rhulen

On both sides of the Atlantic, Loam Wolf reviewers were invited to ride the highly anticipated SRAM Eagle Powertrain eMTB system. Our First Ride Review will cover media events from two of the four brands that have aligned themselves with the new SRAM Powertrain eMTB motor and new Auto Shift and coast shifting features. While our time on the system is not extensive, we put it to the test with some intense laps and came away with a good idea of how it is likely to perform and who it’s likely to suit. Of course, we look forward to getting some long-term units to test the reliability and see if SRAM’s tuning with Brose have led to a more robust and durable motor than the Specialized Levo’s we often hear so much about. Keep reading for our first impressions of the system, followed by the press release with SRAM’s low-down on the details.  

The Wolf’s First Impression

Initial impressions aboard the SRAM / Brose unit are promising. With countless hours riding drive units from competitors, and especially the largely similar Brose drive unit found in Specialized eBikes, it feels to have the same characteristics as that Specialized unit but with some vague and misty claims of durability improvements made by SRAM. The Brose drive unit has consistently ranked highly in our testing thanks to its grunty low-cadence torque and natural feeling response. Similar to the Specialized Brose unit, the tone of the SRAM drive unit is lower than most on the market, but it’s not stealthily silent – you know when it’s working hard for you.   

To simplify the experience further, and likely because it was easier to make it work with their AXS pod, riders will have the choice between two power modes. Range and Rally will help riders focus on maximizing range or having a more powerful, high-speed ride. At first it seemed a bit of an issue however we then reflected back on our hours riding and found that if we’re not in Boost/Turbo then we’re likely in a more eco-friendly mode, not toggling around between three or more settings. We agree that only having two modes is likely to split opinions, but it’s worth noting that riders can tune each mode in their app, so they can find better middle-grounds for their mileage and ride preference. For Robert, he prefers the ability to choose between a larger range of modes on-the-fly to obtain the power and range balance that he desires more acutely, but Max is satisfied and believes that two modes is enough. SRAM’s approach here is suitably inkeeping with the simplicity of the rest of their Eagle Powertrain eMTB system. Using the AXS app, it’s likely riders will be able to find a setting for Range that keeps them happy for the vast majority of the time, with Rally reserved for…well, Rallying. Time and some head-to-head testing will tell exactly how the SRAM Eagle Powertrain drive unit performs, but for now we’re confident in saying it’s a well performing option.   

Chances are we’ve all been riding long enough to feel competent in changing our gears manually, to keep eBike motors and our bodies in their ideal cadence range. It rarely feels like a chore to press a shifter to tailor the gear ratio to the trail. However, SRAM’s push to bring Auto Shift technology to their new Eagle Powertrain eMTB system has us thinking that before too long, we may see shifting gear manually as a task reserved exclusively for bikes with lower-tier components. Crazy isn’t it? Our first rides have left us impressed generally by the ability of the Eagle Powertrain system to tailor the gear range effectively to the trail, especially with the Coast Shift tech going about its business to change gear without us needing to pedal. It’s an awesome feeling to trust the drivetrain (sorry, “Transmission”…) to be in the correct gear when you begin pedaling, and for the most part SRAM’s new system manages to do exactly that. However, it’s not perfect.  

The majority of trails around the world are fairly predictable and consistent, with the gradient and your resulting speed changing gradually. And for this majority of the time, Eagle Powertrain blends your drivetrain into the background and leaves you only focusing on braking and pedaling as you attack the trail ahead, negating the need to touch the AXS pods apart from to change saddle height. However, extreme situations like when we shoot photos and videos for our reviews; session small portions of trail over-and-over; or just some of the more interesting trails where the terrain is constantly undulating, quickly expose the inability of SRAM’s Auto Shift tech to read the trail ahead like the rider can. By no means is Eagle Powertrain’s reaction time slow, but when you go from a fast descent to a steep pitch of climb, you’re left with a lot of gears to change, and so SRAM’s tech being reactive instead of predicting the terrain ahead leaves you crunching your way in either direction of the cassette to get back to the cadence you desire, with the motor often bogging down at ultra-low cadence or your legs spinning like crazy.   

The weaknesses of the SRAM Eagle Powertrain’s reactive approach can be overcome by overriding the Auto Shift using the shifter Pod, giving the system a helping hand for extreme situations. It’s not a problem with the SRAM system as such, as you can still make it up and down the trail without ever touching the shifter, but for gear shifting to become truly autonomous something is likely going to have to change to account for the unpredictable nature of some e-Mountain Biking. SRAM’s Eagle Transmission can feel slow for shifting over a large number of cassette cogs, but crucially hasn’t skipped a beat when it comes to the accuracy of these shifts, regardless of the power being applied to the chain by your legs and motor. This makes the downfalls of the new Eagle Powertrain eMTB system much easier to stomach, and unless you’re looking for the ultimate speed on the most dynamic and unpredictable trails without touching the shifter, it’s safe to say SRAM has done a great job. For us, as it stands, we’ll likely set Auto Shift to “off”, making use of the excellent Coast Shift tech and a little bit of our brain power to ensure we’re always in the right gear, or at least treat the system as if it is off and actively help the gear changes regularly. 

Overall, the new SRAM Eagle Ecosystem is a very interesting experience and is symbolic of the evolution of bicycle technology. Whether we like it or not, the future is here and mountain bikes are not isolated from the electronification of life. While more rigid single speeders may be rolling over in their proverbial graves, we’ll be open-minded enough to put these gears and components through the paces for some long-term reviews coming soon.

PRESS RELEASE

SRAM EAGLE POWERTRAIN

Removing the front derailleur.
Removing the wires.
Removing the derailleur hanger.
Removing barriers.
Now, with Eagle Powertrain, we’ve removed the compromises.

GO FOR EAGLE POWERTRAIN.

The complete, seamless and holistic E-MTB system designed to turn on uninterrupted flow.

Go for the better ride.
Eagle Powertrain is inspired innovation, radical simplicity, unmatched integration with Eagle Transmission, clean and
simple rider control, and AXS enabled personalization.

Go for power applied properly.
Go for fun.
Go for the most natural ride experience ever.

FO FOR UNBELIEVEABLE EASE.

Full Power. Fully in your control. The Eagle Powertrain power tune applies natural feeling, traction generating, technical move completing, controllable power to the rear wheel. Developed and proven with BlackBox athletes and profiled to work in concert with how real riders, like you, actually pedal.

Only possible with Eagle. With Eagle Transmission the harder you pedal, the better it shifts. Nowhere is this more apparent than when paired with Eagle Powertrain.

GO FOR SEAMLESS INTEGRATION.

An elegant system that works together.

Total. Pod. Control. The versatility of AXS pod controllers lets you assign all powertrain rider commands – without the need to compromise the bar with the clutter of additional remotes and bar mounted displays. What’s left? The ultra-clean and intelligent wireless cockpit, indicative of any Eagle AXS system.

Better Batteries. Better everything. The unique Eagle Powertrain battery streamlines the interface between battery and drive unit. Delivering even more power in a smaller area and super elegant form factor for more pleasing frame silhouettes.

GO FOR PERSONALIZED CONTROL.

A fully integrated AXS ecosystem allows new levels of personalization for Eagle Powertrain.

Push your buttons. Layout your cockpit exactly as you desire – AXS makes it possible to assign Pod buttons.

Spin to win or crank it out? Both. Fine tune the feel of Eagle Powertrain Auto Shift features for terrain or how you’re feeling.

Power, in the palm of your hand. The Eagle Powertrain AXS App makes the off-bike experience as rich as the on-bike experience.

GO FOR THE WIN.

Eagle Powertrain has already won the toughest race series out there: The UCI EWS-E. Cloaked by the Blackbox wing, but exactly like the Eagle Powertrain system available today.

Born from Blackbox. Riding with Eagle Powertrain, Yannick Pontal (BlackBox Test Pilot Program) became the reigning champion in the 2022 EWS-E series. His feedback partnership with our engineers and development team allowed SRAM to build a race-winning system at home on the circuit and on your local trails.

“Our focus is always on the rider first. The goal of the system was to provide the rider with a complete, wireless, integrated E-MTB system tuned specifically for performance mountain biking. We simplified the ride allowing the rider to focus on the trail.” – Michael Hemme // E-MTB Category Manager

CONTROLS

AXS BRIDGE DISPLAY

INTUITIVE RIDER EXPERIENCE
The Eagle Powertrain AXS Bridge Display is the sophisticated nerve center of the entire system, giving you a control unit that greatly simplifies the experience. Think of it as an onboard extension of the AXS App, providing everything in a brilliantly illuminated, full color, waterproof display, protected under Gorilla Glass.
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Power (short press): Service Mode / motor support off
Power (long press): On and Off
AXS (short press): Switch between Range and Rally modes
AXS (long press): Open and close pairing session

PODS

FAMILIAR CONTACT POINTS
Toggle between Range and Rallymodes. Control your Rockshox Reverb AXS dropper post. Press and hold to multi-shift Eagle Transmission. AXS control, encompasses everything.
—
LONG PRESS (PRESS AND HOLD)
R1: Auto Shift On/Off
R2: Auto Shift adjustment
L1: Hold for Push Mode
L2: AXS dropper actuation

SHORT PRESS (PRESS AND RELEASE)
R1: Shift rear derailleur outboard
R2: Shift rear derailleur inboard
L1: Switch between Range and Rally modes
L2: AXS dropper actuation

“Our Auto Shift algorithm is like a bike’s sixth sense, deciding when to shift so riders can stay laser-focused on their ride. It’s not just smart tech, it’s the ultimate riding companion.” – Dominique Fuss and Victor Freyssinet // Electrical and Software Engineers

GO FOR FEELING SUPER. AND HUMAN.

Auto Shift. When you want. What could feel more natural than not having to think about shifting while you ride? Eagle Powertrain Auto Shift is a feat that senses and translates rider input to deliver an incredibly intuitive experience. Planning an attack or simply want to override the system? Auto Shift seamlessly accepts rider commands, to be ready for your next move.

Shift while coasting. Eagle Powertrain Coast Shift allows the chainring to move freely from the cranks, letting you shift while coasting. Why? Opening the possibilities of shift anywhere performance (whether pedaling or not) puts you in total control, even when the terrain ahead isn’t.

TWO WAYS TO GET THE MOST.

RANGE AND RALLY
Reducing complexity with two support modes that can be easily adjusted and customized for individual desire. Where others give you unnecessary power modes and confusing names, Eagle Powertrain uses just two.

• Range Mode | With the touch of a Pod button, toggle to Range Mode for longer routes, easier terrain or when conserving power is a good move.
• Rally Mode | Toggle to Rally Mode for shorter rides or whenever you want access to the capabilities of power. Keep it simple.

“It was an incredible opportunity to develop a fully holistic system. All components–from the display to the derailleur–forming one perfectly synced unit. Our wireless AXS technology enabled us to create features like Auto Shift, Coast Shift and the limitless options of Eagle Transmission provide shifting under full load.” – Sebastian Dueweling // Chief System Engineer

COMPACT AND FULL SIZE BATTERY

Powering the Eagle Powertrain. Utilizing a unique C-shaped clip-in or optional slide-in interface, the Eagle Powertrain Battery helps to support partner OE manufacturers in their quest to keep the weight low and centered. It comes in at a 630Wh compact or 720Wh full size and is easily removable with a single allen key.
—
630WH COMPACT SIZE

• Sportive, low center of gravity
• 3KG
• Cell 21700
• Tilt-in mount

720WH FULL SIZE

• Maximum range
• 4,1KG
• Cell 21700
• Slide-in mount

Charging times with the standard
4A charger from 0 to 100%

• 720Wh battery = ~5 hours
• 630Wh battery = ~4.5 hours

SRAM DRIVE UNIT

Powered by Brose

So much more than merely a motor, the Eagle Powertrain Drive Unit has been engineered with a reimagined power delivery tune that replicates a far more natural pedaling experience. It’s a feel only made possible by our holistic approach to the entire system, where we called upon proven motor hardware and paired it with Eagle Transmission. It’s an approach that took learnings from short-comings that plague other motors, such as common power losses from super-hard riding, and gave us the opportunity to go further by utilizing things such as heat-resistant materials that provide superior thermal performance and enable longer power delivery.
—
SRAM unique software tune
Up to 90Nm of torque
680W peak power
Best in class derating (heat vs. power loss)
Natural ride feeling
Quiet

Everything in control with the AXS App. The Eagle Powertrain AXS App makes the off-bike experience as rich as the on bike experience. From customizing drive unit power output to simply checking battery life while off the bike, the AXS App lets you view and fine tune a host of features, right from your phone.

Learn more by visiting SRAM.com