Like all mountain and gravel bike components, e-bike mid-drive motors can’t escape riders' desire for lighter weight and more compact packaging. Although Shimano’s new e-bike motors are targeted at commuter bikes, the reality is that many commuter routes now include detours through parks, making the case for commuter bikes with larger volume off-road tread tyres. Many e-bike adventure and gravel bike riders also used their bikes in a dual-purpose role, for commuting and off-road touring, creating an audience for these new mid-drive motors. 

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Two new e-bike drive units

The larger and more potent of Shimano’s new mid-drive motors is EP5. Rated at 60Nm, this compact mid-drive motor weighs only 3kg. 

Engineers and product specialists at Shimano have targeted the EP5 at commuters, but it also has real applicability for adventure gravel riders. Especially those off-road touring riders who believe in the merits of an internally geared hub. The EP5 supports Shimano’s Auto Shift feature, meaning if your adventure gravel e-bike features an internally geared hub or Auto Shift-compatible rear derailleur, you can use autonomous shifting. 

2025 shimano ep 5 explode.jpg, by Liam Mercer

Configurability is crucial with any e-bike mid-drive motor, and EP5 has 15 unique assist characteristics that allow for fine-tuning. The E-TUBE PROJECT app allows riders to personalise their level of assistance, but like many other e-bike drive components, the EP5 disengages once speeds reach 28mph. Shimano estimates its EP5 will provide 270km of assistance across a primarily flat routing. 

For riders who desire something a touch lighter and have superior fitness to compensate for a slight motor output reduction, there’s the E5100. Rated for slightly less torque at 50Nm, the E5100 prioritises low weight and quiet pedal assistance. 

At only 2.4kg, it’s significantly lighter than an EP5 mid-drive motor, but features the same level of power assist customisation via an app and your connected smart devices. The E5100 has a lower disengagement threshold than the EP5, at 20mph, and it is only Auto Shift compatible with IHG drivetrains. 

Shimano’s new mid-drive motors work on bikes regardless of brake specification. That means you can run an EP5 or E5100 on bikes with V-brakes, discs, roller brakes or coaster brakes. 

2024 shimano ep 5 hero 1.jpg, by Liam Mercer

For riders who see the value in a true dual-purpose adventure or gravel e-bike, capable of commuting in the week and adventuring over weekends, the EP5 and E5100 mid-drive motors could be a desirable solution. 

• shimano.com

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