Even the humble bicycle hasn't escaped the clutches of modern technology. A whole herd of new e-bikes with electric motors are taking to our cities' streets. Adding a motor to a standard cycle does ramp up the price significantly, but it takes much of the effort out of cycling, making your commute to the office a sweat-free experience and allowing you to sit back and enjoy your suburban cruise.
Again, these are base level components here. The Shimano/TX55 gearing is fine for this application level but I have lost my chain a few times in a few weeks. The frame is surprisingly solid aluminum alloy which feels stiffer and lighter than last year’s Ancheer. The supplied front 10W light is very bright, however the back light is charged via USB and has a push button rather than being wired into the controller. The disc brakes are the same no-name brand as the Ancheer but appear to be a size bigger. The fork, while not amazing, is a big improvement in stiffness and give over the Ancheer’s, which scared me a bit.
Available products (motors, senors, batteries, control systems. etc.) change fast since the e-bike market shows a strong growth. In principle, get a rear motor if you want a lot of raw power and acceleration (e.g. for a 500W motor). Middle motors are more energy efficient and less subject to problems (e.g. overheating). Middle motors usually are combined with integrated rear hub gears, and rear motors with derailleurs. Both have advantages and disadvantages. E.g. the former require less maintenance, are easy to use in go-and-stop traffic, but require taking off weight on pedals when shifting. Therefore the latter (derailleurs) are better for speedy overland and hills cycling.
Electric motor assisted bicycles have been banned in the State of New York and are not permitted for on-road use. It appears the only known allowance of an electric bicycle is if it is an electric powered moped, at this time. There is a proposed bill to allow ebikes. As of May 2009, Bill A2393("Defines the term electric assisted bicycle") has been passed in the NY State Assembly and its corresponding Bill S4014, sponsored by Senator Thomas Morahan, is before the NY State Senate.
There are individuals who claim to have lost considerable amounts of weight by using an electric bike. A recent prospective cohort study however found that people using e-bikes have a higher BMI. By making the biking terrain less of an issue, people who wouldn't otherwise consider biking can use the electric assistance when needed and otherwise pedal as they are able. This means people of lower fitness levels or who haven't cycled in many years can start enjoying the many health benefits E-bikes have to offer. 
I would advocate you ride legal within the laws of your state. I would also look into some kind of liability rider or umbrella policy with your home owner’s policy, which covers your personal liability and theft. Get your bike registered; wear your helmet, eye protection, whatever is required by state law so that if an accident occurs and you are at fault, there is no legal recourse. Even if you own a 750W/20mph ebike that meets the definition of a bicycle, any at-fault cyclist may still be denied coverage by stingy insurance companies who want to support their clients. Your health insurance will usually cover your medical bills, but the costs of an expensive ebike may be lost.
This is a virtual hello to all the people who came by our booth last weekend at the BC Bike Show and are just now visiting our webpage for the first time. We had a great time and were delighted to see how much this event has grown recently. (And to those who lament that the bike show is now totally taken over by ebikes, well it's been over 15 years now that we've been trying to tell you all this day was coming!)
Range is a key consideration with electric bikes, and is affected by factors such as motor efficiency, battery capacity, efficiency of the driving electronics, aerodynamics, hills and weight of the bike and rider. The range of an electric bike is usually stated as somewhere between 7 km (uphill on electric power only) to 70 km (minimum assistance) and is highly dependent on whether or not the bike is tested on flat roads or hills. Some manufacturers, such as the Canadian BionX or American E+ (manufactured by Electric Motion Systems), have the option of using regenerative braking, the motor acts as a generator to slow the bike down prior to the brake pads engaging. This is useful for extending the range and the life of brake pads and wheel rims. There are also experiments using fuel cells. e.g. the PHB. Some experiments have also been undertaken with super capacitors to supplement or replace batteries for cars and some SUVS.
The legal definition/description of an electric bicycle is most closely described in the code as a "motorized scooter" in that it is powered by an electric motor and/or human power . It may be also be described as a "Motorized bicycle". However, that description does not include electric powered motor specifically. And it appears that the legal definition "Motorized Bicycle" and "Motorized Scooter" are in conflict. Motorized bicycle is a pedal bicycle which has a helper motor, or a non-pedal bicycle which has a motor, with a cylinder capacity not exceeding fifty cubic centimeters, an automatic transmission, and which is capable of a maximum speed of no more than thirty miles per hour. A motorized bicycle shall not be operated upon any way, as defined in section one within the commonwealth by any person under sixteen years of age, nor at a speed in excess of twenty-five miles per hour. A motorized bicycle shall not be operated on any way by any person not possessing a valid driver’s license or learner’s permit. Every person operating a motorized bicycle upon a way shall have the right to use all public ways in the commonwealth except limited access or express state highways where signs specifically prohibiting bicycles have been posted, and shall be subject to the traffic laws and regulations of the commonwealth and the regulations contained in this section, except that the motorized bicycle operator may keep to the right when passing a motor vehicle which is moving in the travel lane of the way, and the motorized bicycle operator shall signal by either hand his intention to stop or turn. Motorized bicycles may be operated on bicycle lanes adjacent to the various ways, but shall be excluded from off-street recreational bicycle paths. Every person operating a motorized bicycle or riding as a passenger on a motorized bicycle shall wear protective headgear conforming with such minimum standards of construction and performance as the registrar may prescribe, and no person operating a motorized bicycle shall permit any other person to ride a passenger on such motorized bicycle unless such passenger is wearing such protective headgear.
Both the Stromer and the Stoeckli are very nice looking designs and easy to handle. Reliability for both does not seem to be up to Swiss standards, e.g. some of the 2012 Stöcklis seem to have bad contacts. However, as of 2013, most of these problems should be fixed. The Cube got criticized for its battery/saddle system, but this has probably been fixed in more recent edition and it has less "punch" then the other's since the motor is smaller (324W?). I don't know about the BH Neo Nitro. Given the relatively low price of the BH Nitro, it may be the best buy in this category if you plan to cover smaller distances (the battery is limited to 9Ah, and Spain's industry does need some help ;) Anyhow, all of these models come with a variety of motors and country-specific modifications. E.g. in France, the BH Nitro comes with a 350W motor and is electronically limited to 25km/h, whereas in Switzerland you either can get a 500W - 45 km/h version or a 250W? - 25km/h version.
Being member of European Economic Area (EEA), Norway implemented the European Union directive 2002/24/EC. This directive defined legal ebikes for all EU and EEA countries to cycle "with pedal assistance which are equipped with an auxiliary electric motor having a maximum continuous rated power of 0.25 kW, of which the output is progressively reduced and finally cut off as the vehicle reaches a speed of 25 km/h or if the cyclist stops pedaling." The definition became part of Norwegian vehicle legislation in 2003. A more detailed specification will become effective when the new European ebike product safety standard EN 15194 is published in 2009.
However, Emu sells a little foldable number if that's your bag. The Emu Crossbar is for town commuters that require a sweet ride that's backed up by solid Shimano Nexus hub gears and Tektro brakes, which are adequate if not the best on the market. Riding is smooth and easy, with the crank moving sensor doing its best to iron out any gaps in power delivery.
If you're more concerned with conquering the countryside than the commute, Cyclotricity's Stealth is the one for you. It's a full-size mountain bike, with aggressive tyres and suspension on the front forks to absorb the rocks and bumps on the trails. It's comfortable to ride, and its motor can either give you assistance while you ride, or you can just hit the throttle to rocket over hills with no effort on your part.
The oldest patent for an electric bike I've been able to find at the US Patent and Trademark Office is this one, by Ogden Bolton, Jr. of Canton Ohio, which was filed in September 1895 and granted three months later. You can see from these original diagrams that it bears an amazingly close resemblance to modern electric bikes. In the general picture on the left, you can see there's a hub motor on the rear wheel (blue), a battery suspended from the frame (red), and a simple handlebar control to make the thing stop and go. In the more detailed cutaway of the hub motor on the right, you can see there's a six-pole magnet in the center (orange) bolted to the frame and an armature (made from coiled wire, yellow) that rotates around it when the current is switched on. It's quite a hefty motor even by modern standards; Ogdon mentions "a heavy current at low voltage—for instance, to carry one hundred amperes at ten volts." So that's 1000 watts, which is about twice the power of a typical modern bike hub motor.
The $3,099 MSRP is a bit daunting if you've not shopped for high-end bikes before, but it compares favorably with, say, Trek's electric bike lineup. That said, you can get a solid urban/commuter bike without a motor for well under $1,000. You can even score an e-bike for under a grand, but you'll likely be looking at a battery range of less than 40 miles, along with lower-quality components.
Brock had been running his esoteric shop on Cambie St. for over 30 years, pioneering the sale and production of recumbent bikes, tricycles, velomobiles, unicycles, and of course electric bicycles well before any of these things were popular. He was dabbling with early ebike conversions in the 1990's when we were still in grade school and has been for many years one of the few shops always willing to say yes to electric retrofits. We hope to still see him riding around streets of Vancouver in a white velomobile.
China's experience, as the leading e-bike world market, has raised concerns about road traffic safety and several cities have considered banning them from bicycle lanes. As the number of e-bikes increased and more powerful motors are used, capable of reaching up to 30 miles per hour (48 km/h), the number of traffic accidents have risen significantly in China. E-bike riders are more likely than a car driver to be killed or injured in a collision, and because e-bikers use conventional bicycle lanes they mix with slower-moving bicycles and pedestrians, increasing the risk of traffic collisions.
This 150mm-travel e-mtb tackles big descents, shines on flowy trails, and provides the boost you need for the trip back. Pedal assist comes from Shimano’s 6.2-pound STePS E8000 motor with a 20mph boost. Shifting is motorized too, with Shimano’s exemplary XT Di2 drivetrain providing the most precise and consistent shifts a mountain bike can have. The fun comes from the E-Core’s 150mm of front and rear travel courtesy of a RockShox Yari fork and Deluxe RT shock. Both can be locked out for long, fire-road type climbs, though on an e-bike that feature feels less necessary.
On the other hand, the battery doesn’t lock into the bike, which means you can’t just leave it on your bike when you park at the bike rack. Anyone could walk by and simply remove your battery. That seems like an oversight to me, though perhaps the designers assumed that such a small battery would just be easy to take with you. And it is. My wife could probably lose this battery in her purse.