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: 

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.
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.
There are no ADRs applicable to AA or AB category vehicles. There are ADRs for lighting, braking, noise, controls and dimensions for LA category vehicles, mostly referencing the equivalent UN ECE Regulations. An approval is required to supply to the market any road vehicle to which ADRs apply and an import approval is required to import any road vehicle into Australia.[5]

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.
"Electric-assisted bicycle" means a bicycle with two or three wheels, a saddle, fully operative pedals for human propulsion, and an electric motor. The electric-assisted bicycle's electric motor must have a power output of no more than one thousand watts, be incapable of propelling the device at a speed of more than twenty miles per hour on level ground, and be incapable of further increasing the speed of the device when human power alone is used to propel the device beyond twenty miles per hour.[66]
Electric bicycles are not allowed in any public area, meaning an area where there is full or partial public access. Any kind of pedal assist, electric bike, scooter, moped or vehicle which has any form of propulsion, whether in full or as assist, other than human power, must be approved as either a car, motorcycle, van, truck, bus or similar. This makes pedelecs and tilt-controlled two-wheel personal vehicles illegal in all practical ways, as they cannot be registered as a motor cycle.[36]
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.
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.