SRAM enters the e-bike game with all-new Powertrain

It's been rumoured for some time that SRAM was working on it own e-bike motor platform, and it is finally here with automatic shifting and AXS integration

09:40, Monday 2nd October 2023

Alex Hunt

Junior Tech Writer

SRAM Powertrain e-bike system includes automatic and coast shifting

The new SRAM Powertrain joins the ever-booming e-bike market with a little more up its sleeve than some of the existing competition. Built around offering more than just pedal assistance, the Powertrain system has been developed specifically around electronic drivetrains and the AXS ecosystem in general.

One of the most noteworthy inclusions in the design of Powertrain is that it has been optimised for automatic shifting, as well as shifting whilst not pedalling.

Although SRAM will initially be rolling out Powertrain to four e-mountain bikes to begin with, the technology and AXS integration could be something that we could see crossing over into e-gravel or e-road bikes in the not-too-distant future.

SRAM Powertrain is controlled by a wireless pod leaving the cockpit tidy and the AXS bridge aesthetically pleasing

The motor unit itself is the work of drive unit specialists Brose who have also worked on motors for the Specialized turbo range of e-bikes. The motor has been designed to produce 90Nm of torque and a maximum of 680 watts of power putting it as a class leader in this respect. To power the motor, SRAM are offering two battery sizes to choose from, 630Wh and 720Wh, with the option to add a 250Wh range extender if epic all-day rides are your thing.

SRAM has named the control unit of the system the AXS Bridge display and wirelessly communicates with the motor and any other additions to the AXS ecosystem that you may have on your bike. The display can be controlled by a bar-mounted control that is also wirelessly connected to the bridge.

Range or Rally

Bucking the trend somewhat compared to other competitors SRAM has slimmed down the modes available to the rider. The two-tier system has been labelled as range and rally, the idea behind the move to this pared-down user system is to declutter and simplify the experience for the rider.

Range - As the name would suggest, this mode offers the best in regards to battery management. This mode is best suited to longer rides or on less demanding terrain.

Rally - This will provide the most pedal assistance for challenging terrain and for shorter rides as this mode will have a reduced range. This can be compared to a turbo or boost setting in a more traditional e-bike system.

Auto shift is here

Although auto shift might not be anything new to the world of cycling, with Landrider offering an ‘auto shift’ system back in the early 2000’s this level of integrated auto shifting is something new, especially for SRAM.

Shimano does offer a level of auto shifting on their e-bike platforms however with the partnership of the new T-Type transmission platform SRAM offers and the new powertrain motor automatic shifting is customisable and developed to work with the specific increased demands a motor will put through a drivetrain.

Auto shifting with SRAM T-Type groupsets is said to work seamlessly under load

Using the SRAM AXS app, the auto shift parameters are customisable to your riding preference. The cadence at which shifts happen can be tailored in the app depending on the ride you are going on.

Dominique Fuss and Victor Freyssinet, electrical and software engineers at SRAM, have this to say about the auto shift feature: “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.”

Coast shift also makes an appearance with the powertrain, allowing the shifting of gears whilst the rider freewheels. Adding this feature is ideal for mountain biking as it allows riders to change gears, when riding through technical terrain that isn’t conducive to pedalling. This is achieved by isolating the chainring from the cranks allowing it to have free movement.

Let us know your thoughts on this new system and if you are interested in automatic shifting or if you prefer to make the choice yourself. Comment below to join the conversation.

SRAM

SRAM is a components manufacturer based in Chicago, Illinois. The company mainly produces drivetrains, for a wide variety of disciplines, alongside many other components. SRAM’s has acquired other brands within the industry such as Zipp, RockShox and Quarq.