Shimano release the new EP8 eMTB motor for 2021

Shimano EP8
(Image credit: Merida / Ian Lean)

Shimano has put its long-running Steps E8000 format to pastor and heralds in its EP8 motor unit for 2021. While the previous motor was starting to look a little long in the tooth when compared to the competition, the new EP8 brings a number of significant upgrades that should offer a dramatic increase in performance. 

The headline specs are the bolstered power output and increased battery size. Upping the motor power by 15 Nm, the Shimano EP8's 85Nm maximum power output matches that of Bosch's updated motor to offer an increase in acceleration and support when riding extreme terrain. The battery has also been expanded with a capacity of 630Wh which is claimed to give the same range as the previous version in Trail mode and increase the range in Eco. The larger 630Wh battery is claimed to take 50% charge in 2.5 hours and taking 6 hours to full charge if using the EC-E8004 charger.

To better manage the extra grunt of the EP8 motor, Shimano has refined the delivery of power in Trail mode. Self-adjusting based on rider input, the Trail mode offers a progressive output meaning the harder you pedal the more support is provided. In-turn when riding at a lower cadence, for example when tackling crux sections on technical climbs that may require some finesse, the motor should reflect the gentler pedal strokes and limit the risk of losing rear wheel traction.

Not only is the power delivery more natural but the drag has been reduced by a claimed 36%, which should save energy when sprinting over the assist limit or make riding home on a drained battery less of a chore after having too much fun on the trails. 

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There are physical improvements as well. The unit is noticeable smaller which increases ground clearance when rolling over trail features and gives a sleeker integration into the frame. The 177mm Q-factor is the same found on Shimano's non-assisted drivetrain and the EP8 uses a Hollowtech shaft for reduced weight but increased stiffness. However, the most notable physical attribute development is the one you cant see. 

Shimano has managed to shave a hefty 300g over the previous generation model with the EP8 tipping the scales at 2.6kg, around 190g lighter than Bosch's equivalent motor. Weight plays a significant role in how a bike rides and this reduction in motor weight will please riders who are looking for a more playful feeling eMTB. Part of this is down to the magnesium body which saves weight, adds extra protection to the motor and reduces operation noise.

We are fans of Shimano's neatly positioned screen and simple E7000 assist switch which is easy to use whilst remaining tucked away from potential crash damage. The EP8 ditches the 'Firebolt' style shifter in favour of an updated E7000 with more of a concave button shape for better ergonomics.

Motor behaviours can be tuned using the Shimano E-Tube app and now there are also two motor profiles which can be used to quickly switch between different configurations if you ride different types of terrain.

And by far the most important update, it appears Shimano has resolved the error code W013 which occurs when the bike is turned on and there is pressure on the pedals.

Shimano EP8 Merida eONE SIXTY 9000

Merida eONE SIXTY 9000 for 2021 is equipped with Shimano's EP8 motor (Image credit: Merida / Ian Lean)

Shimano's EP8 motor will be specced on a range of top brands 2021 eMTB's including the majority of Merida's ebike range which benefits from the extra performance of the EP8. Merida's eONE-SIXTY EP8 / 630Wh battery-equipped eMTB's start from around €4.200 / £ 3,800, and EP8 / 630Wh battery-equipped e-hardtails from around €3.500 / £ 3,200.

Merida's eONE-SIXTY frame, geometry and mullet layout has proven successful and remains unchanged from last year. The Merida eONE-SIXTY 9000 we have in for test features a slightly beefed-up spec over last year that should cause no concerns for even the hardest charging riders. The Fox 36 Factory has been replaced with a Fox 38 Elite adding stiffness and precision to the front end whilst the 3C EXO+ tyres have been swapped out for extra protection of Maxxis' Double Down casing.

We were big fans of the Merida eONE-SIXTY Limited Edition we reviewed earlier in the year and expect the added performance from the EP8 motor will further complement the eONE-SIXTY platform's all-round capability, a full review of the Shimano EP8 motor and Merida eONE-SIXTY 9000 will be available on Bike Perfect soon. 

Graham Cottingham
Senior reviews writer, Bike Perfect

Graham is all about riding bikes off-road. With almost 20 years of riding experience, he has dabbled in downhill, enduro, and gravel racing. Not afraid of a challenge, Graham has embraced bikepacking over the last few years and likes nothing more than strapping some bags to his bike and covering big miles to explore Scotland's wildernesses. When he isn’t shredding the gnar in the Tweed Valley, sleeping in bushes, or tinkering with bikes, he is writing tech reviews for Bike Perfect.

Rides: Cotic SolarisMax, Stooge MK4, 24 Bicycles Le Toy 3, Surly Steamroller

Height: 177cm

Weight: 71kg