The first functioning electric motor was displayed in the early 19th century, though the device constructed by British scientist Michael Faraday did little more than swirl a wire around a magnet when an electric charge was introduced. Still, the concept proved that electricity could do work. Functional electric motors would follow in many forms after that achievement in 1821. Soon scientists and tinkerers around the world, including visionaries such as Nikola Tesla, were experimenting with all manner of electric motors -- some worked with DC power, others with AC. By the end of the century, myriad electric motors had been produced, capable of exerting enough force with enough reliable control that they were practical for use in myriad applications.
Photo: Zap Electric's power-assist kit turns a conventional bike into an electric one. There's a bolt-on DC electric motor (weighing just over 3kg or 7lb) just above the back wheel, behind the police officer's foot, pressing against the tire and driving it by simple friction. The motor's powered by a compact lead-acid battery (weighing about 5.5 kg or 12 lb) inside a protective nylon bag. This kit adds quite bit of weight to the bike, but gives extra range and speed when needed. Photo taken in Santa Rosa, California by Rick Tang courtesy of US DOE/NREL.
"Electric power-assisted bicycle" means a vehicle that travels on not more than three wheels in contact with the ground and is equipped with (i) pedals that allow propulsion by human power and (ii) an electric motor with an input of no more than 1,000 watts that reduces the pedal effort required of the rider. For the purposes of Chapter 8 of this title, an electric power-assisted bicycle shall be a vehicle when operated on a highway.
Because the power is applied through the chain and sprocket, power is typically limited to around 250–500 watts to protect against fast wear on the drivetrain. An electric mid-drive combined with an internal gear hub at the back hub may require care due to the lack of a clutch mechanism to soften the shock to the gears at the moment of re-engagement. A continuously variable transmission or a fully automatic internal gear hub may reduce the shocks due to the viscosity of oils used for liquid coupling instead of the mechanical couplings of the conventional internal gear hubs.
Whether squeezing onto the 4 train or pedaling through Lower Manhattan, I notice a few curious glances at the bike with the big battery in the center of the frame. This is not surprising; e-bikes are huge practically everywhere but the US. According to the latest figures from the Confederation of the European Bicycle Industry, e-bike growth in the UK is up from 40,000 units in 2016 to 63,000 in 2017.
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!)
Motor-driven cycles may be operated on the roadway without registration, but the operator must have a driver's license. The cycle may not be operated on any sidewalk, limited access highway or turnpike. If the maximum speed of the cycle is less than the speed limit of the road, the cycle must operate in the right hand lane available for traffic or upon a usable shoulder on the right side of the road unless the operator is making a left turn.
Bicycles featuring pedal power were developed during the subsequent decades of the 19th century, with the most emblematic example being the bicycle we know today as the Penny-Farthing. The bike was named based on the substantial difference in its wheel size resembling the larger and smaller Penny and Farthing coins, respectively. These bicycles were wildly popular among the well heeled upper classes of Europe and America despite their penchant for launching riders head first over the large wheel, not to mention their relative difficulty to mount and dismount.
The Class 3 Aventon Pace 500 urban e-bike has five levels of pedal assist and tops out at 28 mph. But the Pace has something not found on a lot of modern e-bikes. In addition to pedal power, it also has a throttle—in the case of the Pace, a small thumb paddle on the left side of the handlebar next to the control unit that holds at a steady 20 mph, no pedaling required. The bike itself has an aluminum frame, a swept-back handlebar, ergo grips, a sturdy kickstand, hydraulic disc brakes, 8-speed Shimano Altus shifting and gearing, 27.5x2.2-inch Kenda e-bike-rated tires, a saddle the size of Texas, and good ol’ classic city/commuter-bike geometry. It doesn’t come equipped with fenders or a rear rack, but you can add them. Power comes in the form of a 500-watt rear-hub motor, a semi-integrated battery on the down tube (with a range of up to 50 miles), and a backlit display unit mounted on the stem.
During the course of its evolution, the Specialized Levo has helped shape the world of eMTBing. When it was introduced, it set the benchmark in riding dynamics and integration. Now Specialized has completely redesigned the bike and put it on 29″ wheels. The integration has been improved yet again, the battery capacity has been increased and the handling has been refined. We were thrilled with our first test ride. Anyone looking for a new bike next year for maximum trail performance should definitely take a closer look at the new Levo! We’re already looking forward to our big group test of the best bikes of 2019 early next year.
Electric bikes are considered motorcycles in Hong Kong, and therefore need type approval from the Transport Department, just as automobiles. All electric bikes available in Hong Kong fail to meet the type approval requirement, and the Transport Department has never granted any type approval for an electric bike, making all electric bikes effectively illegal in Hong Kong. Even if they got type approval, the driver would need a motorcycle driving license to ride. As a side note, Hong Kong doesn't have a moped vehicle class (and therefore no moped driving license), and mopeds are considered motorcycles too.
Simple, convenient, cheap, and economical—bicycles are one of the world's favorite forms of transportation. But they're not for everyone. They can be hard to pedal up and down hills or with heavy loads, and elderly or disabled people may find them impossible to manage. In the last few years, a new generation of electric bicycles has begun to revolutionize our idea of environmentally friendly transportation. These new cycles have all the convenience of cars with all the simple economy of ordinary cycles. Let's take a closer look at how they work.
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. 
The Consumer Product Safety Commission(CPSC) stipulates that commercially manufactured low-speed electric bicycles, or tricycles, must have fully operable pedals, an electric motor not exceeding 750W of power and a top motor-powered speed not in excess of 20 miles per hour (32 km/h). An electric bike remaining within these specifications will be regarded simply as a bicycle for purposes of safety standards. This supersedes any state law that is more stringent, but only regarding safety equipment required on electric bicycles and the standard of manufacture they must meet.. The legislation enacting this amendment to the CPSC is also known as HR 727.
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.
E-bikes are classified in three different types: Class 1 and Class 3 bikes are powered proportionally to the “input” a rider gives via pedaling. “It feels natural, and you’re still riding a bike, so all your reflexes, skill and comfort you’ve developed over years of riding bikes apply immediately,” says Fritz Rice, sales manager of Gregg’s Cycles, near Greenlake.
The European Committee for Standardization (CEN) also has a specific Technical Committee, TC333, that defines European standards for cycles. Their mandate states that EN cycle standards shall harmonize with ISO standards. Some CEN cycle standards were developed before ISO published their standards, leading to strong European influences in this area. European cycle standards tend to describe minimum safety requirements, while ISO standards have historically harmonized parts geometry.
The motor isn’t insanely powerful, but it gets you up to full speed quickly enough. I never felt like the bike was underpowered. The motor does make more noise than a lot of other hub motor bikes I’ve ridden though. There’s a definite whirrr to the motor caused by the internal plastic gears. While all geared motors will have some level of gear noise, this one stuck out more to me than others.
At just 36V and 5.2 Ah, the battery is not designed for long distance travel. GOTRAX claims the Shift S1 has a range of up to 15 miles (25 km), though that’s only with a lower pedal assist level. If you’re going full throttle, 10 miles (15 km) is a better estimate. But with a battery this small, you could easily charge it at your desk or in the corner of the classroom – lengthening your effective range.
Electric-assisted bicycles are treated as human-powered bicycles, while bicycles capable of propulsion by electric power alone face additional registration and regulatory requirements as mopeds. Requirements include electric power generation by a motor that cannot be easily modified, along with a power assist mechanism that operates safely and smoothly. In December 2008, The assist ratio was updated as follow: