Oregon Law (ORS 801.258) defines an electric assisted bicycle as an electric motor-driven vehicle equipped with operable pedals, a seat or saddle for the rider, no more than three wheels in contact during travel. In addition, the vehicle must be equipped with an electric motor that is capable of applying a power output of no greater than 1,000 watts, and that is incapable of propelling the vehicle at a speed no greater than 20 miles per hour on level ground.[54]
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.
Speaking of which, if you're used to non-electric cycles, be aware that e-bikes are heavy and capped at 25kph or 15.5mph. In many cases, that means the bike starts to feel like its actively fighting against you, if you try to push the speed higher than that by pedalling. That's especially true with heavier bikes, for obvious reasons, and can take a while to get used to. 
Generally they are considered vehicles (like motorcycles and pedal cycles), so are subject to the same rules of the road. Regulations may define maximum power output and for electric bikes may or may not require an interlock to prevent use of power when the rider is not pedaling. In some cases regulatory requirements have been complicated by lobbying in respect of the Segway HT.
This dexterous electric dirt bike is recommended for anyone over the age of 14. It’s fitted with double suspension and big tyres to help you tackle tough terrain. You also get a good selection of gears, that gives you optimal control. The Razor can go as fast as 15 mph on average, and comes with an excellent braking system. The aesthetics are on point, and the racer look is sure to impress. Don’t forget your helmet!
The last 8 months we've been wrapping up some long duration testing of Statorade across different hub motor lines and performing experiments confirming its long term stability. These results have us pumped to introduce this motor cooling solution beyond DIY'ers and into wider markets. As an example, have a look at the video we below showing the effect this has on a small direct drive folding bike motor.

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.
To qualify as an electric-assisted bicycle under state law they need to have a seat and fully operable pedals for human propulsion, meet federal motor vehicle safety standards, an electric motor that has a power output of not more than 1,000 watts, maximum speed of not more than 20 mph (electric motor and human power combined), disengages or ceases to function when the vehicle’s brakes are applied, two or three wheels
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.
The pedals on a motorised bicycle must be the primary source of power for the vehicle. If the motor is the primary source of power then the device cannot be classed as a motorised bicycle. For example, a device where the rider can twist a throttle and complete a journey using motor power only without using the pedals, would not be classed as a motorised bicycle.
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 bikes are becoming a convenient and fun way to commute around a city, but they can be pricey. The average e-bike can cost $3,000, with some models getting up to $5,000 or more. But these prices are dropping, as new models come onto the market — and if you don’t mind giving up some of the glossier, high-tech features like embedded digital displays, retractable cable locks, and and theft tracking and recovery, you can find a really good quality e-bike for under $1,500.