Electric motorized bicycles can be power-on-demand, where the motor is activated by a handlebar mounted throttle, and/or a pedelec (from pedal electric), also known as electric assist, where the electric motor is regulated by pedaling. These have a sensor to detect the pedaling speed, the pedaling force, or both. An electronic controller provides assistance as a function of the sensor inputs, the vehicle speed and the required force. Most controllers also provide for manual adjustment.

There are many possible types of electric motorized bicycles with several technologies available, varying in cost and complexity; direct-drive and geared motor units are both used. An electric power-assist system may be added to almost any pedal cycle using chain drive, belt drive, hub motors or friction drive. The power levels of motors used are influenced by available legal categories and are often limited to under 750 watts.
October 5, 2009 — Ontario is bringing in some new safety requirements for electric bikes. E-bikes, which can reach a speed of 32 kilometres per hour, are allowed to share the road with cars, pedestrians and other traffic throughout the province. The new rules limit the maximum weight of an e-bike to 120 kilograms, require a maximum braking distance of nine metres and prohibit any modifications to the bike's motor that would create speeds greater than 32 kilometres per hour. Also, riders must be at least 16 years of age, wear approved bicycle or motorcycle helmets and follow the same traffic laws as bicyclists. Municipalities will be able to decide where e-bikes may be used on their streets, bike lanes and trails. E-bikes will not be permitted on 400-series highways, expressways or other areas where bicycles are not allowed. Riding an e-bike under the age of 16 or riding an e-bike without an approved helmet carries fines ranging from $60 to $500. For all other traffic offences, e-bike riders will be subject to the same penalties as cyclists.
The other motor is the G311, a front equivalent to the wonderfully silent G310 rear motors we introduced late last year. This motor will be replacing the G01 hub for our front mini geared kits. It's a tad lighter (2.3kg), much quieter (spiral gears!), but still has the features from the G01 that we loved. That means a side cable exit, ISO disk rotor compatibility, and 10mm round axle.

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.[38] 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%.[39][40] In terms of the ratio of cargo weight a bicycle can carry to total weight, it is also an efficient means of cargo transportation.
Electric-assist and other "motorized bicycles"[86] do not need to be inspected, do not require a license, and do not require registration. The vehicle must meet all of the following criteria: a post mounted seat for each person it is designed to carry, two or three wheels which contact the ground, fully operative pedals, wheels at least 16 inches in diameter and a motor not capable of propelling the device at more than 20 mph on level ground. The driver does not need a license, but must be at least 16 years old. DC law prohibits motorized bicycles from traveling anywhere on the sidewalk or in the bike lanes. DC Regulation 18-1201.18 provides: "Except as otherwise permitted for a motor vehicle, no person shall operate a motorized bicycle on any sidewalk or any off-street bikepath or bicycle route within the District. This prohibition shall apply even though the motorized bicycle is being operated solely by human power." So, if cars are prohibited in a particular place, motor-assisted bikes are also prohibited.[87]
Motor-driven cycles may be operated on the roadway without registration, but the operator must have a driver's license.[85] 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.
The aluminum, step-through eJoy is the happy medium between traditional-looking townies that don’t transport much more than the rider and often cumbersome cargo models that are sometimes a challenge to store. With 26-inch wheels, full fenders, a Shimano Alivio nine-speed drivetrain and disc brakes, a wheelbase similar to the average townie, and a big, comfy seat, it has the appearance of a practical everyday cruiser. But its oversize rear rack, silent Bosch Active Line motor, heavy-duty head tube with front-tray mounts (the tray is an add-on), integrated Supernova E3 lights, and roll-over-anything balloon tires hurtle it into hmm-this-could-actually-replace-my-car status. It’s one of the quietest, most convenient, most stylish, and easiest-to-operate e-bikes available.

Oklahoma the following restrictions on the operation of Electric-Assisted Bicycle in 47 O.S. 11-805.2 [123] as follows: 1. Possess a Class A, B, C or D license, but shall be exempt from a motorcycle endorsement; 2. Not be subject to motor vehicle liability insurance requirements only as they pertain to the operation of electric-assisted bicycles; 3. Be authorized to operate an electric-assisted bicycle wherever bicycles are authorized to be operated; 4. Be prohibited from operating an electric-assisted bicycle wherever bicycles are prohibited from operating; and 5. Wear a properly fitted and fastened bicycle helmet which meets the standards of the American National Standards Institute or the Snell Memorial Foundation Standards for protective headgear for use in bicycling, provided such operator is eighteen (18) years of age or less.
But the whole is also influenced by the sensory systems which are very different from model to model. E.g. A typical 2013 Panasonic system requires pedalling for optimal support (55/minute?) and has both a pedalling frequency and a speed sensor. You don't get much assistance if you pedal very slowly or very fast. Typically, a rear motor has a force sensor, i.e. you get lots of support fast when you start pedalling in a low gear, i.e. it will "feel" your need for assistance.
We need to support and put our purchasing power behind ebikes sold in the U.S. that are trying to comply with the California rules which allow 500w and 750w nominal motors and establish 3 classes. If these bikes can create a big enough footprint in the market then future U.S. bike rules may universally adopt these standards. It is better than engaging in regulation showdowns without any standardized and unified proposal on the part of the Electric Bike Community.
The electric bike revolution is spreading across the continent, 2017 data clearly underlines that eBikes are the preferred mode of mobility. 720,000 eBikes were sold in Germany, and KTM are one of the largest producers in their native country. As the market prospers, more and more manufacturers are jumping on the bandwagon than ever. KTM … Continue reading Best KTM eBikes 2018 – The Fully Charged Picks
A human traveling on a bicycle at low to medium speeds of around 16–24 km/h (10–15 mph) uses only the power required to walk. Air drag, which is proportional to the square of speed, requires dramatically higher power outputs as speeds increase. If the rider is sitting upright, the rider's body creates about 75% of the total drag of the bicycle/rider combination. Drag can be reduced by seating the rider in a more aerodynamically streamlined position. Drag can also be reduced by covering the bicycle with an aerodynamic fairing. The fastest recorded unpaced speed on a flat surface is 144.18 km/h (89.59 mph)[41]
Perhaps the cleverest thing of all about the Electric Brompton is that despite all the extra stuff, it folds up exactly the same as the non-powered variety. It's so simple, and unlike certain folding bikes we could mention, what you're left with is a genuinely small thing, rather than something that's about the size of a bike with the front wheel taken off.