BH eMotion electric bikes are based in Spain, and due to the good performance and reasonable price points of their products, they have been doing well in North America over these past couple of years. They are now selling factory turn-key All Wheel Drive models, and I’ll tell you why I think this is a good thing that was way overdue.
[header pic is courtesy of Blue Monkey Bicycles, in Utah…thanks, Duane!]
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Beistegui Hermanos, BH
Back in 1909, in Europe, there had recently been a great deal of innovation in the design of firearms, and the governments of many countries realized there was a need to modernize their armies in order to survive. Three brothers from the Beistegui family in Spain (Cosme, Domingo, and Juan) formed a business and gained a government contract to manufacture modern pistols. BH stands for Beistegui Hermanos, which means the “Beistegui Brothers” in English.
As soon as World War One ended, there was a sudden drop-off in the demand for new pistols, so in 1919, they switched to a product that was suddenly in great demand…bicycles!
In 2008, this company launched their “Easy Motion” (eMotion/Emotion) electric bike line, which has proven to have a very successful balance between features, performance, and affordable price. Now, in 2016…this is the first model year that BH has begun selling All Wheel Drive (AWD) ebikes. We wrote about 2WD ebikes a year ago in January 2015, and I still believe in them now as much as ever.
The power limit in the USA is 750W for a street-legal ebike. And…although AWD ebikes are most appropriate for off-road conditions (where there is NO legal power limit), lets use 750W as our example. On dry pavement, it is unlikely that a single 750W hubmotor (or mid drive) will ever break loose due to overpowering the traction available to one tire. However, as you begin raising the power of your ebikes’ system, you will reach the limits of traction at some point, and…the more slippery the road conditions, the easier the tires will slip at even lower power levels.
Even if we still limit our discussion to 750W, by spreading that limited amount of power across two tires, you not only double the traction of the powered tires, you dramatically raise the amount of heat-shedding that your system is capable of, because now, your amp-heat is being shed by two motors. Not to mention the benefit of redundancy, meaning…if one motor or controller fails, the other can still get you home. Also, two smaller hubmotors are much more stealthy compared to one larger hubmotor…
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BH has two AWD Models now, what do they have in common?
I highly recommend that the best option for an AWD ebike that runs 28-MPH or less (45 km/h), is to seriously consider a geared hubmotor for the front. Our thrusted friend “Doctor Bass” has stated he has run up to 2000W through his front hubmotor before occasionally experiencing tire slippage.
When a powered 2-wheeler accelerates, the weight of the bike will shift to the rear, so…the rear tire can experience more grip (especially on an uphill), and…if you agree that an occasional 2000W peak for the front hubmotor is the effective traction limit, then that power level is well within the range of geared hubmotors, which have good low-RPM torque, and are smaller and lighter than the average 2000W direct drive hubmotor.
As a result of that weight-shift to the rear, it is useful to make the rear motor of an AWD system larger than the front, regardless of the power level of the whole system. There are two features that jumped out at me as I read the specs on the new BH Evo AWD ebikes. The front motor is geared, and the rear motor is larger than the front. Although the rear 350W and front 250W motor “power ratings” are not hugely impressive (due to their primary European Union market target), the 600W total is their continuous rating, and they are both actually capable of a higher temporary peak power.
As I read on, I was pleasantly surprised to find a third feature that really caught my eye. The electronic brain of these ebikes constantly tracks the individual speeds of the motors (perhaps through the hall-sensor pulses?), and if it detects a more than 5% difference in speed, it reads that as one of the wheels beginning to slip. If that happens it will moderate the speed of the faster motor. In plain language, the BH Evo AWD ebikes have “anti-skid” traction control!
I was also quite impressed with their front and rear “quick disconnect” levers. The pic below shows the front geared hubmotor, the 180mm brake disc, and also the dual QD levers that they are using instead of axle-nuts (which would require a wrench). I like how when you combine a QD with a front disc brake, it becomes very easy to remove the wheel for storage, transport, or for fixing a flat tire….without any tools.
Pic courtesy of Mark at ebikereviews.com.au
Both of these models use an aluminum alloy frame that has an attractive hydro-formed shape. They also route their brake cables and shifting cables through the inside of the frame tubing for an uncluttered look. They both use Tektro hydraulic discs (180mm front, 160mm rear), with ebike power cut-offs when activated. They both use 36V batteries that are mounted inside their downtubes.
Those are the similarities, and now…let’s look at how they are different.
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Evo Snow 29 Pro
29-inch wheels are a recent phenomenon, and I’ve been told they have two benefits that make up for the extra weight of the larger wheel and tire. First, they handle potholes and obstacles better than a smaller diameter wheel. Second…if you see an obstacle coming up, you have time to begin adding power to your forward acceleration, and then, once you hit the obstacle, the “flywheel” effect of the larger diameter wheel will help carry you over it.
Regardless of any claimed benefit, 29’r wheels have become quite popular, and the first BH AWD model I want to describe is the Evo Snow 29 Pro. The retail price is $3299, and it uses 29 X 2.25 tires. Its weight is 57.7 lbs (26.2 kg)
The battery is listed as 432-WH (36V/12-Ah), and power can be applied up to 20-MPH (40 km/h), which I assume makes it street-legal in the USA. I found that the “bent” top bar is a well-done variation of the current trend in frame shapes, to make the “standover” height safer. If you are riding on a frame like this and your feet come off of the pedals, hopefully…your feet will hit the ground before your niblets hit the low top bar.
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Evo Big Bud Pro
This fatbike model has all the benefits of the 29’r, but the major difference is that it uses 26 X 4.0 fat tires combined with a solid steel fork, instead of the suspension forks found on the 29’r. This fat version costs about $200 more (at $3499), but you also get a larger battery, presumably because fatbikes typically have a higher rolling resistance in exchange for the improved traction. This ebikes weight is 63.2 lb (28.7 kg), which is only six pounds more than the Snow 29’r.
There is a small discrepancy in the listings between the North American version and the EU-spec version. The EU version is called the “Big Foot”, and has a 460-WH battery (36V / 12.7-Ah). The North American version is called the “Big Bud” and has a 526-WH battery (36V / 14.6-Ah).
Pic courtesy of Alaska Ebike, thanks Cary.
Whatever power level you choose for your ebike, you can experience better traction in all conditions when splitting that power through two slightly smaller motors (instead of one larger motor), and I am glad to see a major manufacturer finally making a big move into this configuration. You might not feel any difference at all on a test track in nice weather, but once you get into some snow or loose soil off-road…AWD is a completely different experience…
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Written by Ron/spinningmagnets, April 2016
