Shimano’s revamped EP8 e-bike drive system aims to set the bar higher than ever for eMTB performance and efficiency. Bringing together upgraded e-bike motors, recent battery updates and improved software to drive it all, EP8 promises more peak power, quieter operation, less drag, lighter weight, smoother operation and improved integration. Essentially, Shimano EP8 takes STePS to another level in almost every performance category, redefining the flagship of Shimano’s e-bike systems.
Shimano EP8 overhauled & upgraded e-bike / eMTB powertrain
Since the introduction of their original XT-level STePS E8000 e-bike (or rather proper eMTB) powertrain four years ago, Shimano has leveraged their bike drivetrain & electronics prowess in the cycling industry to pretty well dominate the pedal-assist mountain bike market. More recently have Bosch has stepped up their game, going head-to-head against Shimano vying for spec on the top level of e-mountainbikes.
And now EP8 hits back with their second generation of “system-engineered e-bike components” developed specifically for performance off-road e-bikes – improving both on the hardware & software.
EP8 eMTB hardware upgrades
The heart of the new Shimano EP8 system is the revamped EP8 drive unit (the motor) stepping up with a 21% max torque output to 85Nm. While it gets substantially more powerful to propel you up the most technical trail features, with a new magnesium case it is also 10% lighter, shedding 300g (to 2.6kg now) vs. the original E800 motor. Part of that lighter weight also comes from a more compact design that means improved ground clearance and more sleek design integration into e-bike frames.
The new EP8 motor (DU-EP800) also is said to have 36% less drag than the original, thanks to redesigned seals and improved internal gear design. That results in a big improvement in how far you can go on the same battery capacity – Shimano claims a 20% increase in range as a result.
But it will be felt even more so when you get past the 25km/h assist limitation, where together with an updated clutch mechanism, Shimano says EP8 creates a much smoother transition to pedaling under your own power at higher speeds. That’s truly one of the biggest downsides we’ve experienced with many higher power eMTB systems, and something we look forward to testing ourselves – to compare it to the original.
More power. Less drag. Shimano also says the EP8 motors does that with less noise and less heat build up. The top level EP8 is now said to be as quiet as the second tier E7000 (quieter than E8000). And the smaller magnesium shell does a better job of conducting heat away from the motor itself for more efficient cooling, even under max load on extended climbs.
Shimano EP8 – Tech details
The new EP8 motor has a 177mm Q-factor with four alloy cranks arm lengths: 160, 165, 170 & 175mm. Sharing the same frame mounting as E7000 & E8000, the new EP800 motor is optimized for use with 12-speed Shimano rear derailleurs, with three standard chainrings available: 34, 36 & 38T. But of course you can use pretty much any rear derailleur or high-power ready internal hub gear system, too. The new EP8 drive unit even includes the option to bolt-on a special chainguide for extra chain retention.
New EP8 controls & batteries
The new system also gets updated eMTB system controls, including a new 1.6″ color display that allows for customizable setup. It also pairs wirelessly to your smartphone by Bluetooth with the updated E-Tube Project app so you can make changes on the go, and can sync to ANT cycling computers to display gear & battery status.
A new low-profile thumb switch to control modes makes co*ckpit setup easy, working with I-spec mounting to share bar space with a dropper remote, depending on your ideal co*ckpit setup.
The batteries actually aren’t new. Introduced back in May, the new bigger 630Wh batteries already delivered 25% more range to existing setups. And the new but lighter 504Wh batteries promised faster recharge times.
EP8 takes advantage of both recent battery upgrades, now eking outing longer rides thanks to the improved motor efficiency.
EP8 eMTB software upgrades
Improved motor efficiency is a big deal, but Shimano also promises that EP8 software goes even further to deliver a better, “more natural feeling e-mountain bike” ride. Essentially the three support levels get tweaked, and add more customization. Boost mode still give the max toque with the lowest matching rider effort.
But now, Trail mode also reaches the 85Nm peak output when you put in the most torque at the pedals. Keep EP8 in Trail mode and it will give economical, lower power support as you soft pedal along, but will ramp up when you stomp on the pedals thanks to a “smarter assist ratio algorithm”, making it simpler to just set it and forget it in one mode for most regular riding, with resulting extension of range.
Or of course, drop it down to Eco mode to reduce output to 30Nm when you want less support, a tougher workout, or just extended battery range.
E-Tube Project & Ride app customization
On top of the hardware & software on your EP8-equipped e-bike, new E-Tube Project & E-Tube Ride apps give you more customization possibilities from your smartphone. In the E-Tube Project app Boost, Trail & Eco mode outputs can each be individually set at 10 levels from 20-85Nm. And you can program different rider or riding-style profiles so you could flip the e-bike between E-EWS race mode to marathon endurance ride mode to commute to work modes, all from your phone.
In the updated E-Tube Ride, you can monitor all ride data streams from your phone as your connected cycling computer. It adds new live maps and ride history to an updated interface that lets you track your e-bike drive or Di2 system, and of course syncs your rides to Strava.
Shimano EP8 availability?
More so than their conventional drivetrains that rely sole on the cyclist for power, Shimano EP8 e-bike powertrains need an eMTB to hang on.
All of these on eMTB photos we see here are EP8 hanging on an update to the Merida eOne-Sixty which debuted last spring. Merida was a development partner with Shimano for the new e-bike setup, but expect many more eMTBs to get the update, starting from today!
