With more and more commuters and recreational riders turning to electric options thanks to their relative ease of use and effortless performance, it's no surprise that e-bikes are the fastest growing sector in the bicycling industry worldwide. Working by providing pedaling assistance, pedelec mid-mount motor systems are a popular choice for e-bike manufacturers thanks to the performance and economy on offer.
Whilst the market for e-bikes continues to expand, two industry giants have emerged as market leaders in pedelec technology. We managed to get our hands on two of the leading pedelec offerings and set about comparing the mid mount systems from market leaders Bosch and cycling industry heavyweight, Shimano.
The seemingly effortless assistance on offer is arguably one of the biggest draw cards for riders entering the e-bike market. Riding experience for both systems tested was extremely positive, however, and as expected, the power delivery differed between the two, with each system having its own nuances, strengths, and weaknesses.
Each system possesses differing levels of assistance to choose as you ride;
Shimano STePS E6000
Bosch Active Line
At standby level, both systems operate exactly the same as a traditional bike, albeit a heavy one. Offering no assistance, the main difference here is that the Shimano system offered no digital display on this setting whereas all on-board computer functions were accessible on the Bosch head unit.
The Eco setting is optimized specifically for range, with both manufacturers claiming a theoretical range of over 100km. On Eco, the Bosch system matches your effort with an additional 40% of assistance, whereas the Shimano unit kicks in up to 70% assistance for every pedal stroke. The differing level of assistance on offer in Eco mode was apparent between the two with the Shimano system noticeably more responsive when getting up to the governed 25kph speed limit (applicable across Australia). That’s not to say the Bosch system was a slog to get moving, however, with both testers agreeing that power delivery was smoother on the Bosch unit.
Sitting just above Eco, the Bosch unit provides a Tour mode of assistance. Ideal for daily riding and commuting. In Tour mode, the drive unit matches your pedaling effort 100% with a maximum of 40nm of torque on offer. It’s worth noting that this extra assistance does come at the expense of overall range. Over the course of several weeks of testing, range experienced on Tour mode was roughly 60% of the theoretical maximum range than that on offer in Eco mode.
Move up to Sport/Normal mode and both drive units now match pedaling effort 150%. The range is roughly halved when utilizing the additional power, though it must be said, the range drop off was considerably less noticeable on the Shimano system, which could be attributed to the slightly larger capacity battery fitted to our test bike. The additional power on offer made setting off from traffic lights and intersections a breeze with both motors providing a similar feel when accelerating from a stand still. With the increased assistance on offer, the Bosch system made sticking on, or slightly above the governed 25kph speed limit less of a chore on flat roads, which could be attributed to a firmware update that sees assistance scaled down post 25kph rather than cutting out abruptly as was evident with the Shimano system.
Turn the wick up to Turbo/High mode and it’s easy to get a sense of what e-bikes are capable of were they not governed by power and speed limits. Selecting the highest level of assistance on both bikes made light work of steeper uphill gradients, and made riding into a stiff headwind a breeze. With units providing a maximum assistance of 230% (Shimano) and 225% (Bosch) of input respectively, the higher output was perfectly suited to more spirited riding at a higher cadence. With great power comes reduced range though so we found it best to save the extra juice for when we really needed it, not for an e-bike drag race.
Overall, both testers were in agreement that the Bosch unit was exceptionally smooth, just what you would expect from the market leader with a long history of producing high-quality electric motors. The Shimano system was also very commendable with a lot more poke on offer, particularly in eco mode, thanks to the increased power and torque on offer, but lacked some refinement when compared directly to the Bosch unit. However, the power delivery is only one part of the story here.
System Displays and Interactivity
Bosch and Shimano each have a number of different display units and controls across the range of systems on offer. Our test units were supplied with the STePS City cockpit (Shimano) and the Intuvia (Bosch) display and controller.
Bosch has an extensive range of display options that are available to the multiple levels of systems. These range from simple, small clutter free displays, to advanced full color, GPS headunits.
The Intuvia display fitted is the most commonly found option on Bosch supplied e-bikes and for good reason. The display is easy to read in direct sunlight and offered a simple layout of the speed, distance, trip time, assistance level and battery range metrics.
The Intuvia also acted as a charging station for external devices such as smartphones, however, it’s worth noting that power output comes courtesy of a Micro-USB port which will more than likely require an adaptor in order to properly connect to your device.
Shimano offers two different display options, the City designed for light off-road and commuting duties and the MTB for use on electric mountain bikes.
The City display fitted to our test bike was hard to fault, with both testers heaping praise upon the unit. The layout is uncluttered and fuss free and thanks to a high-contrast display, was easily visible in all light conditions. Thanks to Bluetooth compatibility, the head unit can be used to change settings such as Di2 shift frequency and sensitivity and customize the layout via computer, smartphone or tablet.
The controls were easy to use and thanks to their compact size were easily accessible when riding. It is worth noting that our Di2 model featured both left and right controls, which could make for a slightly complicated initial shifting process for uninitiated users.
With a long history in manufacturing quality electric motors for a wide range of consumer products, it's no surprise that the drive unit from Bosch is refined, smooth and a pleasure to ride. The Active line unit fitted to our test bike is the entry level offering from Bosch and provides 250w and 48nm of torque. The power delivery from the unit is smooth and consistent regardless of the assistance level and is relatively noise free in its operation.
The unit itself weighed in at 4.18kg on our trusty Park Tool digital scales, slightly above the claimed 4kg. Whilst the motor tips the scales around 1Kg heavier than the Shimano unit, it was hardly noticeable when out riding in real world conditions thanks to the low center of gravity.
The reliability and quality that are hallmarks of the Shimano range of bicycle components are evident in the industry giant's first foray into the electric bike market. Featuring one of the lightest units on the market and almost silent operation, the E6000 unit tested was very commendable when tested alongside the marked forging Bosch unit.
The E6000 features a total output of 250w with 50nm of torque on offer, whilst this is only a marginal gain over that of the Bosch unit, both testers agreed that the power delivery felt more instant and as such was easier to hold speed regardless of the assistance level.
The motor itself is a smaller unit than the Bosch, and as such weighs in at nearly a full kilogram lighter at 3.16kg, impressive considering the weight savings don’t appear to have come at the expense of any riding dynamics.
Battery Specifications and Options
A motor is only as effective as the power source that fuels it, and luckily enough, both Shimano and Bosch have multiple options to suit all types of e-bike riding.
When Shimano introduced STePS E6000 to the market in 2015, the aim was to target the market dominating Bosch Active Line, matching and improving upon the rival e-bike system in every way.
The battery system is an example of this in action. Base power output for our rack mount battery is quoted at 36v, 11.6 Ah, 418 wh, matching the output figures quoted by Bosch for their powerpack 400 battery. Shimano also offers a larger 500wh battery, however, it is only available for use on the STePS E8000, electric mountain bike system thus far. At the time of publishing this article, battery systems are single mount only, meaning you cannot double up on batteries to increase range, yet (watch this space).
Shimano quote range figures of 150km when used exclusively in Eco mode, 100km in Normal and 70km in High. The range experienced from our test bike was close to the quoted figure, a big tick for the STePS system. Averaging roughly 100km of range per battery cycle when ridden on mixed assistance levels in real world conditions, a large portion of the range savings can be attributed to the cadence sensing assistance on offer, unlike rival systems where you get the same amount of torque regardless of cadence.
Removing and replacing the battery on the test bike was a cinch thanks to the keyless sliding mechanism that locks the battery in place. We couldn’t notice any play from side-to-side when removing and locking the battery in place, a credit to the integrated rack design. Weighing in at a measured 2.59 kg, the Shimano battery matches rival batteries on weight, due to the similar lithium ion plates found inside each of the units.
When is comes to charging the battery itself, a full charge came in at just under 4 hours, bang on the quoted charge time thanks to the 3.1 amp charger provided.
Bosch offers a number of battery options that are compatible with the full range of drive units in the product line. The battery units on offer are the PowerPack 300, 400 and 500, all of which are available in both rack and downtube mount options. The handy thing about the Bosch energy units is the ability to run two batteries in conjunction with each other, effectively doubling range.
The energy source supplied on our Bosch test bike is the familiar PowerPack 400. Featuring 400wh, 36v, and 11ah, the PowerPack 400 was almost identical in specification to the Shimano unit.
Bosch doesn't quote any ballpark range figures, instead opting for a handy Range Assistant. The online tool allows you to input a number of factors that can affect range such as, bike and PowerPack size, right down to wind conditions, cadence and tires used. During the test we experienced around 80km of range from a battery cycle, more than adequate for the majority of riders completing a number of 10-15km commutes or recreational rides.
The battery itself is able to be charged on the bike which is a big plus as the rack mounted battery could prove slightly difficult to remove from underneath the rack for some users, however, the downtube mount battery available on other entry level city bikes is easily removed thanks to the access provided.
Groupset and Components
The Shimano STePS chainset is compatible with a range of 8, 9, 10 and 11- speed hub and derailleur gear systems.
With Shimano operating at the forefront of the bicycle component industry, it’s no surprise that the componentry supplied on the test bike provided was reliable, well built, and efficient when pedaling both with and without assistance. Our bike was optioned with an 8 speed Di2 (electronic shift) internal hub, the fact it had Di2 meant that the “Symptomatic”, or automatic shift function could be engaged.
The Symptomatic system works by judging your speed and cadence, then proceeds to shift into what the system believes is the most efficient gear for you. Whilst this function is handy, both testers remarked that the automatic shifts felt unintuitive, particularly when getting up to speed, giving a clunky feel as the pedelec assistance literally stops to change gear, before kicking back in again, however, were it more refined, it’s easy to see how automatic shifting would be of benefit to a wide range of recreational riders.
Like the Shimano, the Bosch motor-unit is compatible with a range of hub and derailleur gear systems. The Gazelle Orange CX (fitted with Bosch Active Line motor) provided for the test was also fitted with an 8 speed internal hub, however it was operated by a twist shift mechanism on the handlebar, which works effortlessly in conjunction with the electric motor, free of any clunky shifting and provided smooth power delivery.
In an effort to keep our testing as fair as possible, both bikes selected were essentially robust commuters, built to cope with the rigors of the daily commute, albeit with the notable addition of a mid mounted electric motor. Both bikes were almost identical in specification, featuring a rack mounted battery pack, integrated lights and fenders, step through frame, internal hub gearing (Alfine Di2 - Shimano, NuVinci 8 speed - Bosch) and city tyres.
So is there a winner?
When we set about planning this comparison, we initially set out with the intention of playing each of the units off against each other, however, after riding around on both bikes for the duration of the test, it was agreed that the real winner here isn't either Bosch or Shimano – it's you. Both units performed admirably and lived up to what we believe riders should expect from a commuter focused e-bike. The refinement of the Bosch unit reassures riders that the company has been in the electric motor game a long time, but it's clear that Shimano has sat back and watched the market, and then hit the ground running with its offering to the e-bike market
In terms of overall cost, bikes equipped with Shimano STePS E6000 will typically start from around $2,000, while Bosch Active Line equipped bikes start at around $3,000. Given that, if you're on a tight budget, then the Shimano system is likely to present more options. For those just seeking the best, we recommended basing your decision following a test ride of both systems and the differing bikes they may be attached to.
Thanks to Bosch and Shimano for providing the bikes for this test