I was looking at new ebikes on the web recently, and I stumbled across this interesting E-bike. It is designed and produced by the Canadian company “Procycle” (in French-speaking Quebec), and this new eVox model will be marketed under their Miele brand.
I’ve always been a fan of the “feet forward” posture for the rider, after seeing the Rans and Electra Townie bicycles (also the Trek Pure and the Giant Suede). Most common “diamond” frames place the pedals directly beneath the rider, and when you are attempting to climb a steep uphill, this allows you to raise up and shift your body weight from side to side…and doing this is an efficient application of your energy reserves when you are just pedaling.
Such a lay-out also combines well with positioning the handlebars in such a way that the rider is leaned forward, in order to reduce the wind-resistance. This common posture is most well-known from road-racers, similar to the famous riders of the Tour de France.
However, the “beach cruiser” style of frame evolved to its common lay-out due to beach communities being relatively flat. A single-speed (or possibly a 3-speed IGH) is all that was needed to keep the system simple and affordable, and the riders comfort was catered to by having a broad saddle with the pedals positioned halfway between the seat and the handlebars.
“Dutch” style frames are also similar to beach-cruisers for the same reasons, since Holland is famously very flat. For older riders (like me) I have found that the road-racer posture places my upper body weight onto my wrists (which are not as young as they used to be), and they also force me to lean forward. The “leaned forward” posture is very aerodynamic when you are shooting downhill on the French Alps, but it requires a narrow saddle, and it places my lower body weight in a more uncomfortable position while resting on that narrow saddle.
As much as I like the upright Dutch-style posture when the rider is sitting, if you attempt to stand on the pedals…your knees may brush against the handlebars. This is the reason why beach cruiser handlebars have a significant-length of stem jutting forward, and then the handlebars have a long sweep backwards. This is the major difference between a Dutch bike and a beach cruiser, because the beach cruisers are most frequently found with a single-speed, and the bikes are sometimes ridden across the sand. That requires fat tires and the ability to stand on the pedals.
The classic Dutch bike is only made for the street, so they often have narrow tires for the lower rolling resistance, and compact handlebars to save weight and to fit more easily between dense traffic.
When we all get older enough that we begin embracing a more upright posture on our bicycles, we then have the option to choose a wider saddle (if we want). Then, when we add the option of an electric motor…everything changes. From this discussion, we can see the eVox has more in common with a Dutch bike than a beach cruiser, and since there is an electric motor…there should never be a need to stand on the pedals.
You don’t have to be an older rider to appreciate the comfortable posture of a Dutch-style frame with a motor that allows you to conquer hills with a smile (and no sweating). If you are a commuter who wishes to reduce how much you are forced to use your car, then you just might find this combination to be delightful…just as millions of E-commuters from around the world already have.
This frame is worthy of a second glance. It places the battery in the optimum position with its weight solidly attached near the center of the bikes weight balance. The recent expansion of factory E-bike choices these last two years include the Specialized Turbo, the Stromer ST1, and the BH-eMotion…all of which could have located their battery packs anywhere, but they have all chosen to place the weight of the battery pack in the down-tube.
The Pedego company is one of the top-3 retailers of E-bikes in the USA, but they have yet to use their huge sales volume to specify a battery pack that locates the pack in the triangle. Hopefully for them, they will have this as an option someday.
For those companies who do want to place their battery near the center of the bike, it can place a few restrictions on the frame designer. Many years ago, a bike with no top-bar and dual down-tubes was called a “ladies” frame in North America. The European bike culture has been around long enough that they have evolved to call these a “step through” frame, and I am actually happy to see this development. There are an increasing number of new frames being produced that embrace a “uni-gender” description.
One of our favorite cargo-bikes is the Juiced Riders ODK-II. Since a heavily loaded cargo-bike can be awkward when you try to swing your leg over a high seat (and bulky cargo), the ODK only uses a single frame style that is a “step-through” version. I would not be embarrassed to own this frame (or the eVox), in spite of the lack of a debate-ably masculine diamond-frame top-bar.
The Miele sales literature states that there are two sizes of frame, and the smaller version is suitable for rider heights of 4’9″ to 5’7″
The new 2014 Izip E3 Metro cargobike uses a similar shape, as does the NAHBS 2014 Rob English cargobike. The Izip top bar is lower than the eVox, and the Rob English top bar is higher than the eVox, but they both are a similar shape that is halfway between the two classsic “diamond” and “step-through” shapes.
I can’t help but to notice that there is also a growing trend for mountain bikes to have a bent or curved top-tube to increase the “stand-over” height of the bike (like the eVox), which can help both genders to avoid a crotch injury from an un-expected and sudden “un-seating”, which allows your feet to reach the ground before your crotch reaches the top-bar.
If it sounds like I’m really pushing this frame style, I actually do believe the average street-commuter would really benefit from considering this type of frame as a possibility. Many pedal-commuters who want to move up to an E-bike will often start with a diamond-style road-bike frame, simply because that’s what they are familiar with. Another benefit of the eVox is the low seat-height, which means when you are at a stop…your feet will be flat on the ground.
There are a couple of things that separate the eVox from the the mass of generic Chinese E-bikes that have flooded Ebay. This particular E-bike uses a 96V battery, and it also uses a belted left-side-drive with a non-hub motor.
As far as the higher voltage is concerned, we have known for a long time that the majority of the heat that can damage the motor and controller comes from the amps of current. By choosing a system that has higher volts, you can achieve the same amount of power with fewer amps.
Although, it is quite exceptional for Miele to have chosen a system with volts this high. Many affordable commuters have a base model using 36V, and going to just 48V is a logical and common upgrade for their “premium” model. If someone wanted to use higher volts than 48V, the most often seen upgrade is to a 72V system, which allows you to choose from many readily available 72V components.
Miele has reported that the European-spec controller and motor operate on only 2.5-amps in order to attain the 250W goal, and even the original Canadian version would use only 10A to reach 500W.
I suspect the Miele 96V system uses two 48V batteries combined in series. If any of our readers have a Miele eVox, and you have the opportunity to open up some of the parts, please contact us and we would appreciate you allowing us to publish the pictures and details. Others might be bored by these kind of details, but we are fascinated by pictures of the insides of the motors, controllers, and battery packs from new E-bikes.
The two battery size options are listed as a 400-WH (4.1-Ah), or 600-WH (6.2-Ah), with a claimed one hour for a full recharge, and a half charge in just ten minutes. The best available information about the battery indicates the chemistry is LiFePO4 using 30 cells per series group (30S).
Miele advertises that the battery can take a full charge in just one hour, and a half-charge can be achieved in just 10 minutes. This is not as outrageous as it may at first sound, because the of the batteries high 96V system. The designer has stated that the short charging time was a major factor in designing this E-bike to have such a high voltage.
The DynaMe Belt Drive
The left-side-drive is also intriguing, and it is called the DynaMe system. By using a non-hub motor, it has the ability to spin at many more RPMs than a direct-drive hub motor, such as the famous 9-Continents. This improves the efficiency of the system because electric motors perform better at higher RPMs, and you can also get a given amount of power from a smaller motor if you provide some method of gearing to increase the motor RPMs.
This phenomenon is one of the reasons for the popularity of geared hub-motors (such as the eZee, BPM, BMC, and MAC), which use internal gears to typically allow the motor to spin about 5 times faster than the wheel. The Evox, on the other hand, uses a belt and pulley system to reduce the motor RPMs to the wheel speed. Belts are known for running quieter than the gears that are usually found inside a geared hub-motor.
The belt is another odd choice, it is a Poly-V belt. If the rider attempts a sudden acceleration, it may slip some. This can make life easier on the controller, because it mechanically limits the amperage peaks that can be demanded from the rider. But…any slippage that might occur (at the motor pulley) will damage the belt. If any fears that the government may have that E-bike customers may hot rod their E-bikes after the purchase, a Poly-V belt eliminates the possibility of ANY after-market power-boosting. The drive pulleys are only a modest 4:1 ratio.
Due to the modest 500W power of this system (the legal limit in Canada), it would have been a perfect candidate to incorporate a dual parallel right-side drive, like the drive on the eCortina, found here. Such a system would provide the motor and the pedals each with the independent use of the rear hubs 3-speeds. Such a system worked well for the eCortina builder (Roy Prince), until he raised the power of his system enough that…it broke the 3-speed IGH, and he upgraded to a derailler and external sprocket system…which can take more power.
Also, due to how close the USA is to Canada, I would have thought they’d build this system for the USA power limit of 750W, and then limit the amps for a 500W version to be sold in Canada. Perhaps they will have a 750W model in the near future. In spite of these missed engineering opportunities (not giving the motor some gears, no 750W model), the Miele Evox remains a very interesting E-bike with an intriguing feature-set.
There is a dealer for these E-bikes in France, and quite a few in Canada, but I suspect we are unlikely to see many of these on the road. The prices vary, but they are upscale, but…without typical upscale features. The front fork does not have suspension or disc brakes (although a disc brake mount is a part of the fork, meaning it is an option to bolt calipers on). In an upright-posture bike, the rear suspension (or a suspension seat-post) is more important than the front suspension, and the eVox has none of these.
Since the motor is not in the wheel, this bike will have fewer broken spokes and flat tires, and any flat tires that you do get will be easier to fix, compared to a heavy rear hub-motor. The weight of the battery and motor are centrally-located, so the balance of this bike should be very good…compared to E-bikes with the battery and the motor are both in the rear where the “tail wags the dog”. That would be a scary and dangerous situation at higher speeds, and somewhat uncomfortable at low speeds.
Written by Ron/Spinningmagnets, April 2014