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.
In some countries mixed systems, i.e. pedaling and/or using a throttle is legal. In EU countries and Switzerland this is not the case. I.e. you can buy an electric scooter, but this is not considered to be an e-bike in the moped / light scooter category. That kind of hack is probably more difficult, unless the original design has been modified to fit with (s)Pedelec specs. E.g. The Ezee models are of that kind and modifications to revert to the original does not seem to be too difficult...
Parliament has decided to approve the speed pedelec – a type of super electric bike that can reach speeds of up to 45 km/hour – for riding on cycle paths. Danish Parliament has decided that as of July 1 2018 those operating the super bikes only need to have turned 15 and wear a helmet, while the licence and number-plate demands will no longer be in play. 
The federal Consumer Product Safety Act defines a "low speed electric bicycle" as a two or three wheeled vehicle with fully operable pedals, a top speed when powered solely by the motor under 20 mph (32 km/h) and an electric motor that produces less than 750 W (1.01 hp). The Act authorizes the Consumer Product Safety Commission to protect people who ride low-speed electric vehicles by issuing necessary safety regulations. The rules for e-bikes on public roads, sidewalks, and pathways are under state jurisdiction, and vary.
Bicycles offer an important mode of transport in many developing countries. Until recently, bicycles have been a staple of everyday life throughout Asian countries. They are the most frequently used method of transport for commuting to work, school, shopping, and life in general. In Europe, bicycles are commonly used. They also offer a degree of exercise to keep individuals healthy.
The Registrar will permit an electric motor driven cycle to be registered if it meets Canada Motor Vehicle Safety Standards (CMVSS) as a Limited Speed Motorcycle, or Scooter as is done with gas powered motor driven cycles. If the vehicle was manufactured after 1988 it will bear a compliance label stating that it meets these standards. The operator will be subject to all the requirements placed on operators of motor driven cycles.
Maybe the most confusing legal issue facing e-bike riders today is the difference between a bike lane and bike path. A bike lane is a marked section of roadway shared with motor vehicles. Bike paths pretty much universally prohibit the use of motorized vehicles. Still, you will need to research your area. As an example: “A path near our office specifically says “no motorized bicycles.” Yet, when we tracked down an employee who claimed to work enforcement on the path, he said that our e-bike was allowed.”8
The bicycle is extraordinarily efficient in both biological and mechanical terms. The bicycle is the most efficient human-powered means of transportation in terms of energy a person must expend to travel a given distance. From a mechanical viewpoint, up to 99% of the energy delivered by the rider into the pedals is transmitted to the wheels, although the use of gearing mechanisms may reduce this by 10–15%. In terms of the ratio of cargo weight a bicycle can carry to total weight, it is also an efficient means of cargo transportation.
As long as the electric bicycle meets three criteria it is considered a low-speed electric bicycle, or simply a "bicycle." Three criteria: must travel less than 20 mph on flat ground without pedaling, must have functional pedals and must have less than a 750 watt motor. This is the same criteria as Federal Public Law 107-319. I checked my facts with the law office of Spohn, Spohn & Zeigler at 144 East Center Street, Marion, OH 43302 on August 21, 2009. A low-speed electric bicycle does not require registration, insurance, license plates (tags), or a driver's license. The rules of an electric bicycle are the same as a traditional bicycle. There is some confusion caused by Ohio interchanging the word Moped with "motorized bicycle." If a dealer sells you a bike that follows the guidelines of Federal Public Law 107-319, then you have a bicycle. If the bike has no pedals or has a higher wattage motor than 750 watts or can travel faster than 20mph you have a moped or scooter; Ohio requires tags and registration for mopeds and scooters.
When you have the electric motor turned on, it engages with your first push of the pedals. The difference in acceleration is startling compared to any other bike I've ridden. In Eco mode, I could sprint from 0 to 20mph in about 200 feet/65m. Switch to Turbo, and it's about 150/30m feet. As I mentioned above, you still have to pedal. The difference with an electric bike is the feeling of getting more bang for the buck. And if you want to be lazy, you can. Stay in third or fourth gear and you'll be able to stay around 18-19mph with minimal effort. But if you want to go much faster than 20mph, you'll need to work.
It should be noted that the definition as written does not define the power of the motor in Watts as is conventionally done for electric bicycles but rather in brake horsepower. Thus for an electric bicycle, motor kit, or electric bicycle motor that is not rated by the manufacture in brake horsepower but rather in Watts a conversion must be made in the units a conversion which is not given in the code of the law and thus the court will have to consider a factor of conversion that is not directly encoded in the law. Industry standard conversion for Watts to horsepower for electric motors is 1 horsepower = 746 watts. Acceptance of that conversion factor from industry, however, as interpretation of the law is subject to the process of the courts since it is not defined specifically in the law.
China has experienced an explosive growth of sales of non-assisted e-bikes including scooter type, with annual sales jumping from 56,000 units in 1998 to over 21 million in 2008, and reaching an estimated fleet of 120 million e-bikes in early 2010. This boom was triggered by Chinese local governments' efforts to restrict motorcycles in city centers to avoid traffic disruption and accidents. By late 2009 motorcycles are banned or restricted in over ninety major Chinese cities. Users began replacing traditional bicycles and motorcycles and e-bike became an alternative to commuting by car. Nevertheless, road safety concerns continue as around 2,500 e-bike related deaths were registered in 2007. By late 2009 ten cities had also banned or imposed restrictions on e-bikes on the same grounds as motorcycles. Among these cities were Guangzhou, Shenzhen, Changsha, Foshan, Changzhou, and Dongguang.
To operate a motorized/electric-assisted bicycle on the streets or highways a person must have a valid driver’s license or a motorized bicycle permit. A person under the age of 16 operating a motorized/electric-assisted bicycle under a motorized bicycle permit is subject to restrictions of no passengers (a parent or guardian my ride if the motorized/electric assisted bicycle is equipped with a seat and footrests for a passenger), no night driving, driving on any highway marked as an interstate, must wear a helmet, foot rests for passengers (if designed for passenger(s). A motorized bicycle permit is available to persons of at least 15 years of age who have passed the motorized bicycle test or passed a motorized bicycle course. A motorized bicycle would need the same coverage as a motorcycle would in this state. An electric-assisted bicycle would not need coverage.