The Shimano EP8 Motor Is Turning Heads

Shimano’s New EP8 Motor

The EP8 is smaller and lighter than the E8000, allowing for more ground clearance and better frame-design options.


Shimano recently unveiled a new motor aimed for the mountain bike market that will sit atop the E8000 motor that we’ve known for the last few seasons. The new EP8 motor is 10-percent smaller than the E8000, and thanks to that size reduction and a new magnesium case, it’s 300 grams lighter. Shimano says it provides up to 350-percent support (in Boost mode versus the E8000’s 300 percent). There’s 21-percent more torque (85 N/m total) in Trail and Boost modes. One key benefit is that the motor was designed to have 36-percent less drag. 

EP8 motor-side view.


Shimano designed this motor for more support and longer range. A new assist algorithm constantly calculates the ideal assist level for the situation. There’s a walk mode for hike-a-bike sections that helps the bike push itself at 2 1/2 mph.

The claimed performance of this motor, especially the 85 N/m of torque, puts it directly head to head against the likes of the Yamaha PW-X2 (80 N/m), Bosch CX (85 N/m) and Brose S-Mag (90 N/m). Though the EP8 doesn’t feature options like Bosch’s extended support for technical climbs, there’s always the possibility to change that with a firmware update.


Users can change parameters on the system using the E-Tube Project app. We’ve been using that app for a couple of years to tweak the Trail mode on our test bikes as we think the factory setting on the E8000 was way too low. Riders can now select between five levels of startup assistance to go from relaxed, smooth acceleration to a more aggressive takeoff to help with steep climbs. There’s also an E-Tube Ride app, which turns your smartphone into a cycling computer, giving you access to more information, mapping features and more.


“Shimano designed this motor for more support and longer range.”


The new display is an upgrade from the E8000 display and offers a more capable chip set, expanded capability with third-party computers, and the ability to select two different custom ride profiles. 

Shimano will also be introducing two new batteries, both of which have 630 Wh (versus the previous 504 Wh), with one internal and one external. We’d love to see a dual-battery setup in an e-MTB, whether on 504-Wh plus one 630-Wh or two 630-Wh batteries, but that would have to be separate because Shimano doesn’t have a system like Bosch does for multiple batteries.

The full Shimano EP8 system, including (l to r) control keypad, SC-EM800 display, EP8 motor, 630-Wh external battery and the e-Tube app.



The new motor puts out a peak 500 watts, and with the full 85 N/m available to riders in Trail mode, riders can get away with staying in Trail mode more often to allow better range. The motor’s 175mm Q-factor is fairly normal, and there are four different crankarm lengths available—from 160mm to 175mm.

In addition to the reduction in drag, there’s a similar reduction in sound. People refer to the E8000 motor’s sound as that of a small sewing machine. The EP8 should be even quieter, letting riders to better enjoy the solitude of nature as they pedal along.

We have yet to get our grubby mitts on a bike with the new powerplant, but we will probably by the time you are reading this. Stay tuned!

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