The key component of any electric mountain bike (eMTB) is the motor. Here we look at some of the top eMTB motors being used on the best eMTBs.
Fighting for the top position among eMTB motors, Shimano’s STEPS system has gained huge popularity thanks to a few awesome features.
This eMTB motor by Shimano weighs only 2.8kg and also takes up less space than most other eMTB motors with a compact design that integrates nicely with most frames. It also enables the use of shorter chainstays to help make the bike feel more alive.
Thanks to this compact size it also benefits from one of the narrowest Q-factors (the distance between the pedal attachment points) to give bikes an organic pedalling feel.
While the Shimano STEPS only offers 70Nm of torque, the motor provides a powerful level of support regardless of the cadence (pedalling rate). It adjusts this power in a smooth and progressive way throughout the different settings, with no noticeable ‘steps’ as you change through the speeds.
The Shimano STEPs motor has five power-level modes, including a ‘smart terrain mode’ that automatically adapts power levels dependent upon the type of terrain you are riding, which is amazing when you are riding hard and don’t want to think too much.
The STEPS display is one of the most user-friendly and intuitive displays out of its rivals, thanks to the neat visual and color representations of the different power modes. It also sits safely out of harm’s way behind the handlebars, which also provides protection from any crashes you may have.
As long-standing bike component manufacturers, Shimano has sorted the crank interface. A shorter 165mm KT crank runs on a standard Hollowtech 11 bottom bracket. This can run a direct-mount chainring compatible with anything up to 12-speed drivetrains.
Shimano has a single externally mounted 504Wh battery option, however several other manufacturers have designed their own batteries to work with the STEPS motor.
Some electric mountain bikes using this system: BMC, Focus, Ghost, Haro, Scott, Cannondale, Orbea,Pivot, Devinci
Bosch Performance Line CX
Bosch has been pioneering the eMTB motor market for years now and has a dominant market share, especially in Europe. The performance Line CX represents the top of its MTB line, offering the best of Bosch’s technology.
It can provide up to 75Nm of torque, applied through a range of pedalling cadences all the way up to a leg-burning 120rpm.
The Performance Line CX offers more kick on start-up than other motors with an impressive surge of power, especially in Turbo mode. If you have never rode a eMTB before, it comes as quite a shock, be careful…you have been warned!
The main difference between this Bosch eMTB motor and other units is the use of internal gearing rather than a standard chainring operations. While keeping the chain out of the way, it also creates a larger motor that weighs a mighty 4KG -- over 30% heavier than the Shimano STEPS. This large motor size affects the crank width and limits chainstay length options.
The Bosch Performance Line CX display has four power modes, the top two being ‘Turbo’ and ‘Smart eMTB’ -- providing the full 75Nm of power. Electric mountain bikes will change the assistance from 120 to 300 percent, depending on cadence and pedal pressure applied. There is also a handy walk-assist mode for when you really cannot ride or need to rest your legs.
Bosch offer four display options, including the new for 2019 Kiox head unit. Like the Shimano STEPS display unit, it uses changing colors to quickly determine which mode you are currently in. It’s also specifically designed for mountain biking with a scratch-resistant screen and tactile buttons which can be operated with MTB gloves.
Bosch offer a variety of battery options to suit different power needs and frame designs, the most popular being the 500Wh internal PowerTube.
The latest eMTB motor comes from the electronics giant Panasonic, who recently produced the GXO eMTB motor. Currently only available in the USA, this motor is one of the lightest and most powerful in terms of pure torque. With a huge 90NM available, this should translate into an awesome ride.
Panasonic has been a long-term manufacturer of battery cells for existing motor brands like Honda, but now has its own designs built and available. The two main options are the 288Wh version for fast and light rides and the larger 432Wh battery for days out.
The GXO display is centered over the stem of your eMTB, providing good visibility and is connected to a button unit that fitted next to the left-hand bike grip.
Giant Syncdrive Pro/Sport
Giant uses Yamaha’s technology to provide it with exactly the right power for eMTBs. It’s a stripped out version of the PW-X motor to produce a motor weight of only 3.1K. Though the motor is super light rivaling Shimano’s STEPS, it can produce an insane 80Nm of torque and 360% of additional pedal assistance.
The top 3 power modes of Giant’s Syncdrive Pro can support a cadence of up to 120 rpm without any loss of power.
Like the STEPs motor, it uses a standard crank/chainring combination to deliver the Q-factor and nice pedal feel. It also uses a responsive ratchet/bottom bracket system to provide instant power when desired.
Giant’s Ride control Evo head unit sits above the eMTB stem, with a large display being easy to read and navigate while you are riding. The display gives you the battery life as a percentage so you can work out how much power you have left. Panasonic also give you the option to divert power via a USB port to charge your personal electronic devices.
Giant has three specific battery capabilities, but it’s only the larger 400 and 500Wh batteries that are used for eMTBs. Giant’s fast charger technology enables the bigger batteries to be fully charged in around three or four hours.
Brose Drive S Mag
The Brose eMTB motor was used by all Specialized’s turbo models, but was a bit of a beast. The latest Drive S is much more slimmed down, in overall size and mass, while managing to get more power out of the motor -- well done Brose!
The new Drive S mag motor is housed in magnesium, opposed to the more traditional aluminium used by most manufacturers. The Drive S motor has also dropped over ½ kilo in overall weight and is 15% more compact.
The new Brose eMTB motor also has some amazing performance stats too -- like 410% assistance and a max. torque of 90Nm. Brose has developed a new ‘Flex Power mode’, which gives assistance at much higher pedalling speeds.
The Drive S Mag display is stem mounted and offers easy-to-use buttons to provide a full range of data you would expect.
Image sources: shimano-steps.com, brose-ebike.com