Here's a quick rundown of the most popular motors on the market and how they stack up against each other.
It may sound obvious but until you’ve ridden an e-bike you may not appreciate how e-bike motors vary and what it means for your riding experience.
Shimano’s E8000 STEPS motor has been successfully powering some of the best e-bikes for years now, but it’s been eclipsed in terms of power and performance by the competition. Bosch’s
gen 4 Performance Line CX motor
and the Brose S-Mag fitted to Specialized’s Turbo Levo and Kenevo both have more power and can use bigger batteries.
So at long last there’s a successor to the E8000; called the EP8, it boasts an array of improvements over the old unit, including more power, less weight and a whisper-quiet ride. And perhaps best of all, it uses the same mounting points as the old motor, meaning you’re going to be seeing a lot of bike brands upgrade their bikes to the new motor in the next few months. This is great for buyers because it means we won’t have to pick our next e-bike based on its motor, instead it’ll come down to which is the best bike.
The biggest change then is that Shimano has boosted the torque of the EP8 by 15Nm over the old E8000 to bring it in line with the 85Nm Bosch Performance Line CX unit. On paper then, the two are now evenly matched.
It’s made the motor a whole lot lighter too – Shimano has really pulled out all the stops on the EP8 to lose around 300g and 10 per cent volume compared to the E8000. It’s visibly smaller than the old unit, giving additional ground clearance and helping to create sleeker frame designs. There’s also a bigger battery available now, with most high-end full-suspension e-bikes coming with the 630Wh BT-E8036 battery launched earlier this year. This internal battery pack gives an extra 25 per cent range, which should roughly translate into another 200 metres-plus of climbing per ride. Alternatively, if you don’t need the range, Shimano offers smaller and lighter 504Wh versions of both external and internal batteries.
Shimano claims the EP8 is 36 per cent more efficient than the E8000. Or think of it another way, there’s 36 per cent less drag in the motor mechanism. This should mean that you can ride further on the same battery power, that there will be smoother reduction in power when you reach the 25kph limit, and it will be easier to pedal when the motor cuts out.
There have been some sizeable software changes too. You can now access maximum power in Trail mode, something that wasn’t possible on the old E8000 motor, and Eco mode has been dialled to give you more range – an extra 20 per cent on flat terrain compared to E8000. Shimano has also updated its E-Tube app, letting you better customise various parameters in each power mode – things like the torque curve of the motor, the maximum torque in each mode and how quickly the motor reacts to pedalling.
How does it ride? We’ll have a full review coming soon, but our first impressions are good – it’s now got sufficient power to compete, boasts a refined engagement, improved software and a really quiet operation, all wrapped up in a lightweight, compact package. All told, the EP8 is a worthy successor to the E8000.
Bosch Performance Line CX
Bosch has been driving the eBike market for several years and one look at its market share shows how popular the brand is. The Performance Line CX represents the pinnacle of its eMTB line and has the best of Bosch’s technical features built in. It provides up to 85Nm of torque and this is applied through a wide range of pedalling cadences all the way up to a thigh burning 120rpm. The Performance Line CX offers a little more kick on startup than other motors with an impressive surge of power.
This new Bosch Performance Line CX motor and Bosch PowerTube 625 battery were introduced in 2019 offering considerable enhancements over the previous system.
The new magnesium-housing motor is around 50% smaller and 25% lighter than the previous CX motor from Bosch. At 2.9kg, this makes it comparable to the Brose S-Mag, although it’s not quite as light at the new Shimano EP8 (2.6kg).
The smaller size of the unit affords bike companies more freedom to design e-bikes with better geometry and suspension, including significantly shorter chainstays.
The new motor gives out up to 600W of peak power, and Bosch claims that it reacts to the rider’s pedalling without deceleration thanks to multiple sensor design enabling a more intuitive and sensitive response.
There are now four display options from Bosch including the new Kiox headunit. Similar to Shimano’s display, this now uses changing colours to quickly determine which mode you are currently in. It’s also specifically designed for MTB use with a scratch resistant screen, tactile buttons and steerer tube mount. However, none are as sleek and easy to use as the Shimano E7000 switch or Specialized’s modular control units.
Coming in distinctly left of field, German brand Fazua produces a completely different style of motor and battery system. Based around a completely modular and removable system, for many this approach represents the potential future for e-bike design. Called the Evation, this revolutionary system weighs just 4.7kg for the whole kit; that’s battery, motor, drive unit and all associated electronics! Compare that to the main systems where just the drive unit weighs over 3 kilos and you have the possibility for building a very light eMTB. Granted the 1.3kg battery only has a 250Wh capacity but with such a paltry weight you could stuff another in a pack without really noticing it. It also puts out a lower level of assistance than many of the larger units but turn the power off and it’s obvious that the Evation still provides a large degree of assistance. The most interesting aspect though is the removability factor. Promising zero friction with everything removed you can now potentially have one bike to do it all.
The newest kid on the block, electronics experts Panasonic have a freshly introduced eMTB motor, the GXO. Currently only available in the US (but soon to be over here) this unit claims to be the one of lightest and potentially the most powerful in terms of out and out torque. With a whopping 90Nm available, this should translate into a punchy ride with bags of low end grunt. Panasonic has been a long time supplier of battery cells for existing motor brands but now has two internal batteries options of its own design. Choose between the lightweight 288Wh version for fast and light rides on home trails or a larger 432Wh battery for longer forays. The large display is centred over the stem for easy visibility and is connected to a multi-function button unit that sits neatly next to the left hand grip.
Giant Syncdrive Pro/Sport
Giant has completely adapted Yamaha’s existing PW-X motor system to provide it with exactly the right performance features it required. It’s a little more stripped out to produce a motor weight of 3.1kg, that’s pretty competitive currently. Its party trick is its ability to produce up to a leg snapping 80Nm of torque and up to 360 percent of additional assistance. In the top three power modes the Syncdrive Pro can support a cadence of up to 120rpm (110rpm in the lowest two) without any loss of power.
Like Shimano’s STEPS it uses a standard crank/chainring combination to maintain traditional q-factors and pedal feel. It also uses a responsive ratchet/bottom bracket interface to provide almost instantaneous drive.
Giant’s RideControl Evo headunit sits above the stem and has a large display that’s easy to read. It gives battery life as a percentage so you can accurately work out how much power is left and you can also divert power to charge your phone via the in-built USB port.
Giant list three specific battery capacities but it’s only the bigger 400 and 500Wh Panasonic produced batteries that are used for eMTBs. Giant’s fast charger ensures that even the bigger capacity systems can be fully charged in around three hours.
Brose Drive S Mag
The original Brose Drive found traction as the motor used in all of Specialized’s Turbo Levo models but was a bit of a brute. The latest Drive S has been put on a diet, both in physical size and mass, whilst managing to shoehorn even more power into the unit. By incorporating a magnesium housing rather than the more traditional aluminium, Brose has dropped over half a kilo in weight and made the unit 15% smaller.
The Drive S Mag also boasts some impressive performance figures too. How does 410% of electronic assist (it will add four times the effort you apply) and a maximum torque of 90Nm sound? It also has a new Flex Power Mode, which allows assistance at much higher pedalling cadences than ever before. Three display options are available including a larger information-rich unit, a smaller vitals-only display and a button-only option.