Most European bike rules are tight and restrictive. Right now the California state ebike rules in AB 1096 provide the clearest and cleanest format, and they support ebike riding. No other U.S. regulations come close. The big brand ebikes (Giant, Specialized, Trek) are selling bikes that fit within European rules (250w-300w motors). This gives them economies of scale.

The Consumer Product Safety Commission(CPSC) stipulates that commercially manufactured low-speed electric bicycles, or tricycles, must have fully operable pedals, an electric motor not exceeding 750W of power and a top motor-powered speed not in excess of 20 miles per hour (32 km/h).[22] An electric bike remaining within these specifications will be regarded simply as a bicycle for purposes of safety standards. This supersedes any state law that is more stringent, but only regarding safety equipment required on electric bicycles and the standard of manufacture they must meet.[23]. The legislation enacting this amendment to the CPSC is also known as HR 727[24].
Another type of electric assist motor, often referred to as the mid-drive system, is increasing in popularity. With this system, the electric motor is not built into the wheel but is usually mounted near (often under) the bottom bracket shell. In more typical configurations, a cog or wheel on the motor drives a belt or chain that engages with a pulley or sprocket fixed to one of the arms of the bicycle's crankset. Thus the propulsion is provided at the pedals rather than at the wheel, being eventually applied to the wheel via the bicycle's standard drive train.
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.
With a 150mm-travel RockShox Yari fork and 132mm of rear travel from the RockShox Monarch Plus R shock, the Remote CTRL is Kona’s first dual-suspension e-mountain bike. It’s powered by a 250-watt Bosch Performance Line XC mid-drive motor that uses the company’s progressive E-MTB mode that is adaptable to rider input, which means you don’t have to toggle through assistance modes while riding. It offers assistance up to 20 mph, and the 500Wh integrated battery is the largest Bosch currently offers. Beefy 27.5x2.8-inch Maxxis Recon tires offer plenty of traction and also help to absorb smaller hits.

While the first functional battery was developed in the year 1800 by Italian physicist Alessandro Volta, a practical battery would not be seen for several decades yet. By the end of the 19th century, practical and portable batteries were more widely available, this finally freeing the electric motor to be used in a wide new array of applications. It might come as a surprise, but the electric motor, battery, and a bicycle were first paired as far back as the 1890s. It would be approximately 100 years later that electric bicycle development finally entered the mainstream, but the technology and concept behind the electric bike were all in place generations ago.

DON'T BUY THIS BIKE!!!!! Worst customer service ever!!! I bought this bike for my 18 year old son to commute to school. It worked well for the first 2 months but the battery is cheap and stated to wear out. I tried going on the website, but they battery shows as out of stock, and has been for 3 months now. I left 5 emails with customer service, never got a reply. Also there is no number listed on their website to even speak to a real person. Now I have a worthless 5 month old bike..... horrible this company should be ashamed.
One of the items we demonstrated at the show is the new GMAC motor series. This is a powerful clutchless geared hub motor developed over the past 2 years in partnership with MAC motors, using a custom axle with an integrated splined torque arm. Imagine a MAC motor with perfect frame fit for modern bicycles, zero torque transmission on the dropouts, and phenomenal regenerative braking control.
Maryland defines an "electric bicycle" as a vehicle that (1) is designed to be operated by human power with the assistance of an electric motor, (2) is equipped with fully operable pedals, (3) has two or three wheels, (4) has a motor with a rating of 500 watts or less, (5) and is capable of a maximum speed of 20 miles per hour on a level surface when powered by the motor. (Senate Bill 379, approved by the Governor 5/5/2014, Chapter 294.) [96] This legislation excludes "electric bicycle" from the definition of "moped", "motorized minibike", and "motor vehicle", and removes the titling and insurance requirements required for electric bicycles under prior Maryland law.
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:
At the moment this battery is in stock but for local pickup orders only as we are going through the certification testing required for shipping. We've been keeping the 21700 cell offerings on our radar as they start to catch up with the performance specs of the more mature 18650 series and this year it looks like they are finally making the grade. Expect more from us as the year goes on. 
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.[63] The rules for e-bikes on public roads, sidewalks, and pathways are under state jurisdiction, and vary.
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