Since cyclists' legs are most efficient over a narrow range of pedaling speeds, or cadence, a variable gear ratio helps a cyclist to maintain an optimum pedalling speed while covering varied terrain. Some, mainly utility, bicycles use hub gears with between 3 and 14 ratios, but most use the generally more efficient dérailleur system, by which the chain is moved between different cogs called chainrings and sprockets in order to select a ratio. A dérailleur system normally has two dérailleurs, or mechs, one at the front to select the chainring and another at the back to select the sprocket. Most bikes have two or three chainrings, and from 5 to 11 sprockets on the back, with the number of theoretical gears calculated by multiplying front by back. In reality, many gears overlap or require the chain to run diagonally, so the number of usable gears is fewer.
Since cyclists' legs are most efficient over a narrow range of pedaling speeds, or cadence, a variable gear ratio helps a cyclist to maintain an optimum pedalling speed while covering varied terrain. Some, mainly utility, bicycles use hub gears with between 3 and 14 ratios, but most use the generally more efficient dérailleur system, by which the chain is moved between different cogs called chainrings and sprockets in order to select a ratio. A dérailleur system normally has two dérailleurs, or mechs, one at the front to select the chainring and another at the back to select the sprocket. Most bikes have two or three chainrings, and from 5 to 11 sprockets on the back, with the number of theoretical gears calculated by multiplying front by back. In reality, many gears overlap or require the chain to run diagonally, so the number of usable gears is fewer.
State law defines a motorized pedalcycle as a motor-driven cycle equipped with operable pedals, a motor rated at no more than 1.5 brake horsepower, a cylinder capacity not exceeding 50 cubic centimeters, an automatic transmission, and a maximum design speed of no more than 25 miles per hour.[55] Subchapter J of Publication 45 spells out the vehicle requirements in full.
Riding position: You also may wish to check out an e-bike’s riding position before investing in it. For short trips, the riding position might not make much difference, but for long journeys, the upright "Dutch" style with pulled-back handlebars is very comfortable – particularly for tall riders. The same goes for mountain bike styles, though these bikes are not often designed to actually go off-road.
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.[35] 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.
Most electric bicycles can be classified as zero-emissions vehicles, as they emit no combustion byproducts. The environmental effects of electricity generation and power distribution and of manufacturing and disposing of (limited life) high storage density batteries must be taken into account. Even with these issues considered, electric bicycles will have significantly lower environmental impact than conventional automobiles, and are generally seen as environmentally desirable in an urban environment. The small size of the battery pack on an electric bicycle, relative to the larger pack used in an electric car, makes ebikes very good candidates for charging via solar power or other renewable energy resources. Sanyo capitalized on this benefit when it set up "solar parking lots," in which ebike riders can charge their vehicles while parked under photovoltaic panels.[16]
Controllers for brushless motors: E-bikes require high initial torque and therefore models that use brushless motors typically have Hall sensor commutation for speed and angle measurement. An electronic controller provides assistance as a function of the sensor inputs, the vehicle speed and the required force. The controllers generally allow input by means of potentiometer or Hall Effect twist grip (or thumb-operated lever throttle), closed-loop speed control for precise speed regulation, protection logic for over-voltage, over-current and thermal protection. Bikes with a pedal assist function typically have a disc on the crank shaft featuring a ring of magnets coupled with a Hall sensor giving rise to a series of pulses, the frequency of which is proportional to pedaling speed. The controller uses pulse width modulation to regulate the power to the motor. Sometimes support is provided for regenerative braking but infrequent braking and the low mass of bicycles limits recovered energy. An implementation is described in an application note for a 200 W, 24 V Brushless DC (BLDC) motor.[43]
##### Included in this shipment are the much awaited 3540 motors with their slick "UFO" design. These are the replacements for the older square style "H" motors, you may have noticed that this change was implemented last year with the 3525 front and rear motors. As always, we have the motors customized with a 10K NTC thermistor for thermal rollback using the CA3.

```Whether the terrain is flat or hilly impacts the distance you can travel, as does the weight of the bike, your own weight, the gearing available on the bike, and how much juice you give it. We suggest that a distance of 10 to 20 miles is a realistic expectation. Of course, if you're prepared to do at least some pedaling, you can extend that dramatically.
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The 1968 Vienna Convention on Road Traffic of the United Nations considers a bicycle to be a vehicle, and a person controlling a bicycle (whether actually riding or not) is considered an operator. The traffic codes of many countries reflect these definitions and demand that a bicycle satisfy certain legal requirements before it can be used on public roads. In many jurisdictions, it is an offense to use a bicycle that is not in a roadworthy condition.[citation needed]
Let’s face it – Commuting can be a nightmare. Seemingly infinite price hikes, delays to trains, crammed tubes and congested roads dominate the ways of getting to work. The commuter misery is real. But, what if you could transform this part of the day from a chore to a pleasure? Enter the eBike. The clean, … Continue reading Why an eBike is so good for commuting
The "Dandy horse", also called Draisienne or Laufmaschine, was the first human means of transport to use only two wheels in tandem and was invented by the German Baron Karl von Drais. It is regarded as the modern bicycle's forerunner; Drais introduced it to the public in Mannheim in summer 1817 and in Paris in 1818.[18][19] Its rider sat astride a wooden frame supported by two in-line wheels and pushed the vehicle along with his or her feet while steering the front wheel.[18]
The 1968 Vienna Convention on Road Traffic of the United Nations considers a bicycle to be a vehicle, and a person controlling a bicycle (whether actually riding or not) is considered an operator. The traffic codes of many countries reflect these definitions and demand that a bicycle satisfy certain legal requirements before it can be used on public roads. In many jurisdictions, it is an offense to use a bicycle that is not in a roadworthy condition.[citation needed]
Not all e-bikes take the form of conventional push-bikes with an incorporated motor, such as the Cytronex bicycles which use a small battery disguised as a water bottle.[44][45] Some are designed to take the appearance of low capacity motorcycles, but smaller in size and consisting of an electric motor rather than a petrol engine. For example, the Sakura e-bike incorporates a 200 W motor found on standard e-bikes, but also includes plastic cladding, front and rear lights, and a speedometer. It is styled as a modern moped, and is often mistaken for one.[citation needed]
(2) BICYCLE.--Every vehicle propelled solely by human power, and every motorized bicycle propelled by a combination of human power and an electric helper motor capable of propelling the vehicle at a speed of not more than 20 miles per hour on level ground upon which any person may ride, having two tandem wheels, and including any device generally recognized as a bicycle though equipped with two front or two rear wheels. The term does not include such a vehicle with a seat height of no more than 25 inches from the ground when the seat is adjusted to its highest position or a scooter or similar device. No person under the age of 16 may operate or ride upon a motorized bicycle.

Federal law in the United States states that an electric bicycle must have a top speed under 20 mph and a motor which produces less than 750 watts/1 hp. They are not considered motor vehicles by the federal government and are subject to the same consumer safety laws as unassisted bicycles.[11] Their legality on public roads is under state jurisdiction, and varies. See the main Electric bicycle laws article for details on the law in individual states.
Vehicles with an electric power and power of less than 300W are classified as "not a motor vehicle". Such electric bicycles must comply with the same rules as bicycles. You must wear a helmet even on a scooter or bike under 300W. If the power is over 300W or a combustion engine is used it is a "low powered vehicle" and the moped rules apply. Specifically, a drivers license and registration are required.
The headlight/horn is completely frail, and prevents folding the bike. However, the wires broke off within two days (60 miles) of riding, so it wasn't an issue after I removed the light completely. Other than that, it's a great electric bike. I put about 24-40 miles per day on it, and it does the job well. I have steep hills during my ride and it really helps with the effort required to go uphill. The gears only go up to 7, which means that when on flat ground, and pedaling for all that I'm worth, I can only get up to 19 mph before the pedals just spin madly. I pass other cyclists when going uphill at nearly twice their speed, but not so much on flat ground or downhill. The rear has no suspension at all, so I bought a \$50
And let’s not forget the economic advantages of owning an e-bike. The annual cost of running a new family car is, on average, about \$9,000 per year. Running an electric bike costs around \$400 per year. And while filling a gas tank costs around \$30, recharging an electric bike battery costs only about 50 cents. A tank of gas may get you further, but not 60 times further!
Not all electric bicycles take the form of conventional push-bikes with an incorporated motor. Some are designed to take the appearance of low capacity motorcycles, but smaller in size and comprising of an electric motor rather than a petrol engine. Bicycles of note include the Sakura electric bicycle, which incorporates a 200W motor found on standard e-bikes, but also includes plastic cladding, front and rear lights, and a speedometer. It is styled as a modern moped, and is often mistaken for one based on its similarity in appearance.
In addition, Kalk weighs under 155 pounds — less than half of traditional motorbikes. Cake customized parts of the drivetrain and implemented an interior permanent magnet (IPM) motor. On a single charge, the bike travels up to 50 miles and as a bonus feature, maintenance is minimal due to the fact there are few moving parts thanks to its lack of a combustion engine.

In cities where bicycles are not integrated into the public transportation system, commuters often use bicycles as elements of a mixed-mode commute, where the bike is used to travel to and from train stations or other forms of rapid transit. Some students who commute several miles drive a car from home to a campus parking lot, then ride a bicycle to class. Folding bicycles are useful in these scenarios, as they are less cumbersome when carried aboard. Los Angeles removed a small amount of seating on some trains to make more room for bicycles and wheel chairs.[65]
```It appears Tennessee has not passed any legislation that applies to electric bicycles. Some people think the laws pertaining to a Motorized Bicycle should be used for an electric bicycle. However, a Motorized bicycle would be a gasoline powered device per state law as it is defined as "means a vehicle with two (2) or three (3) wheels, an automatic transmission, and a motor with a cylinder capacity not exceeding fifty cubic centimeters (50cc) which produces no more than two (2) brake horsepower and is capable of propelling the vehicle at a maximum design speed of no more than thirty miles per hour (30 mph) on level ground." [56]
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Vehicles with an electric power and power of less than 300W are classified as "not a motor vehicle". Such electric bicycles must comply with the same rules as bicycles. You must wear a helmet even on a scooter or bike under 300W. If the power is over 300W or a combustion engine is used it is a "low powered vehicle" and the moped rules apply. Specifically, a drivers license and registration are required.
Regulations[37] appear to deal with Bicycles with helper motors. No person shall ride a bicycle with a helper motor unless that person holds a valid motor vehicle operator's license. No person shall operate a bicycle with a helper motor at a rate of speed exceeding thirty miles per hour; nor shall any bicycle with a helper motor be operated on any sidewalk, limited access highway or turnpike. Driver's licence is required except if a special permit is obtained by havnig a doctor fill out a certificate and shows they are able to drive the bike with and without the motor assisting.
However, laws and terminology are diverse. Some countries have national regulations but leave the legality of road use for states and provinces to decide. Municipal laws and restrictions add further complications. Systems of classification and nomenclature also vary. Jurisdictions may address "power-assisted bicycle" (Canada) or "power-assisted cycle" (United Kingdom) or "electric pedal-assisted cycles" (European Union) or simply "electric bicycles". Some classify pedelecs as distinct from other bikes using electric power. Thus, the same hardware may be subject to many different classifications and regulations.
It appears Tennessee has not passed any legislation that applies to electric bicycles. Some people think the laws pertaining to a Motorized Bicycle should be used for an electric bicycle. However, a Motorized bicycle would be a gasoline powered device per state law as it is defined as "means a vehicle with two (2) or three (3) wheels, an automatic transmission, and a motor with a cylinder capacity not exceeding fifty cubic centimeters (50cc) which produces no more than two (2) brake horsepower and is capable of propelling the vehicle at a maximum design speed of no more than thirty miles per hour (30 mph) on level ground." [56]
##### Photo: Left: The hub motor of an electric bike. Right: If you took off the casing, this is the kind of thing you'd see. It's a simple brushless motor from a PC cooling fan, but it works in broadly the same way as a bike's hub motor. There's a static part made up of four electromagnet coils (left) and a rotating part (right) made from a permanent magnet (the gray ring) that clips onto it. When the coils are energized in sequence, they generate a magnetic field that makes the permanent magnet and fan spin around. At a glance, a hub motor looks much like an ordinary bicycle hub, but look closer and you'll find it's a lot more bulky.

We spent 45 hours on research, videography, and editing, to review the top choices for this wiki. With rechargeable, battery-powered pedaling assistance, electric bicycles offer an increasingly viable alternative to fossil-fueled commuting, and e-bikes enable riders of various abilities to extend their cycling range. But the street legality of these hybrid machines remains a contentious issue, so be sure to check current state and local laws governing their operation before you hit the road. When users buy our independently chosen editorial picks, we may earn commissions to support our work. Skip to the best electric bike on Amazon.

#### At \$799, it is one of the most affordable full-size folding electric bicycles on the market. There are cheaper folding e-bikes out there, but they generally have much smaller wheels and lower top speeds. With 16″ wheels and a max speed of 32 km/h (20 mph), the Shift S1 combines the specs of higher priced e-bikes with the affordability of a budget folder.

To legally operate a motorized bicycle or electric-assisted bicycle the operator must be licensed, the motorized bicycle/electric-assisted bicycle must be registered in one of the following definitions and meet the required safety equipment. If the operator or the motorized bicycle/electric- assisted bicycle does not meet all requirements, they will not be legal for street/highway use (including the sidewalk).To qualify as a motorized bicycle under state law they need to have motor of a piston displacement capacity of 50 cubic centimeters or less, maximum of two brake horsepower, maximum speed of not more than Template:Convert on a flat surface, fully operable pedals for human propulsion are not required, but may be a part of the machine.
As of May 19, 2009, Nevada amended its state transportation laws to explicitly permit electric bicycles to use any "trail or pedestrian walkway" intended for use with bicycles and constructed with federal funding, and otherwise generally permits electric bicycles to be operated in cases where a regular bicycle could be. An electric bicycle is defined as a two- or three-wheeled vehicle with fully operable pedals with an electric motor producing up to 1 gross brake horsepower and up to 750 watts final output, and with a maximum speed of up to 20 miles per hour on flat ground with a 170 pound rider when powered only by that engine. (AB441, amending NRS 480, 482 and other sections)
We've also released our first native 72V battery pack in a conventional downtube battery casing, assembled using the high power Samsung 27100 40T cells so that even with the small 8Ah capacity it is able to deliver 40-50A continuous currents. This is an ideal battery for fast and sporty offroad ebike builds, allowing powerful performance without the weight or complexity of most 72V setups (either two 36V packs in series or a large triangle frame battery).