This article did a good job of trying to justify the assist speed limits but fell short of detailing how that can ever be effectively enforced. In reality the only enforcement that is going to work is applied speed limits to use of bikes and ebikes. For example, it makes sense that a bike lane on a street that the speed limit of vehicles is the speed limit of the bikes/ebikes. On sidewalks and shared pedestrian paths the speed limit probably does need to be in the 15-20mph range to match traditional bikes speeds on those paths.
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.
In Norway, e-bikes are classified as ordinary bicycles, according to the Vehicle Regulation (kjøretøyforskriften) § 4-1, 5g. Hence, e-bikes are not registered in the Vehicle Registry, and there is no demand for a license to drive them. Still, there are constraints on the bicycle construction. The maximum nominal motor power output can be no more than 250 watts and the maximum performance speed of the vehicle when the engine is running is 25 km per hour (15 mph).[40] A function that reduces motor power when vehicle speed exceeds 25 km per hour is mandatory. However, if the motor is not running, the e-bike, or any other bike, answer only to the constraints of the ordinary speed limits.
How do the State Laws relate to the 2001 Federal Law? This is a difficult question to answer and know how they apply to you individually. From the Federal Law, one would hope that your purchased ebike is simply classified as a bicycle, with all the rights and privileges allotted to a normal cyclist. However, State Laws are confusing because they may be more restrictive in parts and add other requirements. About 30 U.S. states still have confusing regulations around them. Either the bikes are technically classified as mopeds or motor vehicles, or they have equipment, licensing or registration requirements that cause problems for riders. Thanks to the People-For-Bikes/Bicycle Product Suppliers Association (BPSA) partnership with local advocacy groups, they have been able to make the case for streamlining state regulations so that e-bikes are essentially treated like regular bicycles.4
With a chain drive transmission, a chainring attached to a crank drives the chain, which in turn rotates the rear wheel via the rear sprocket(s) (cassette or freewheel). There are four gearing options: two-speed hub gear integrated with chain ring, up to 3 chain rings, up to 11 sprockets, hub gear built into rear wheel (3-speed to 14-speed). The most common options are either a rear hub or multiple chain rings combined with multiple sprockets (other combinations of options are possible but less common).
The handlebars connect to the stem that connects to the fork that connects to the front wheel, and the whole assembly connects to the bike and rotates about the steering axis via the headset bearings. Three styles of handlebar are common. Upright handlebars, the norm in Europe and elsewhere until the 1970s, curve gently back toward the rider, offering a natural grip and comfortable upright position. Drop handlebars "drop" as they curve forward and down, offering the cyclist best braking power from a more aerodynamic "crouched" position, as well as more upright positions in which the hands grip the brake lever mounts, the forward curves, or the upper flat sections for increasingly upright postures. Mountain bikes generally feature a 'straight handlebar' or 'riser bar' with varying degrees of sweep backwards and centimeters rise upwards, as well as wider widths which can provide better handling due to increased leverage against the wheel.
I am very pleased with the quality and performance of this electric bike. I find that the twist grip throtle works better for me than the peddle assist low, medium and high settings. It is not necessary to change out of high gear to climb most hills while peddling with the throttle also providing power. The shocks work well on dirt paths and the seat is comfortable. This bike goes maximum speed up to 19 mph on flat ground. I have
Attitudes to electric bikes have changed in recent years. For a long time they were seen by cyclists as 'cheating' and by non-cyclists as being just like a bike, but uglier and far more expensive. This new breed of best-in-class electric bikes feel more natural, look more normal, and people are coming around to the idea that a ride with the convenience of a bike but without all the sweat and effort is a Very Good Thing. 
Track bicycles do not have brakes, because all riders ride in the same direction around a track which does not necessitate sharp deceleration. Track riders are still able to slow down because all track bicycles are fixed-gear, meaning that there is no freewheel. Without a freewheel, coasting is impossible, so when the rear wheel is moving, the cranks are moving. To slow down, the rider applies resistance to the pedals, acting as a braking system which can be as effective as a conventional rear wheel brake, but not as effective as a front wheel brake.[51]
Electric powered bicycles slower than 20 km/h without pedaling are legally recognized as a non-mechanically operated vehicle in China.[32] According to "TECHNOLOGY WATCH", this should help promote its widespread use.[33] Electric bicycles were banned in some areas of Beijing from August 2002 to January 2006 due to concerns over environmental, safety and city image issues. Beijing has re-allowed use of approved electric bicycles as of January 4, 2006.[34] Some cities in China still ban electric bikes.

Hmm, I think it depends on the forest. My experience has been that if you have a Class 1 ebike and are riding respectfully, most places allow it. I have a sensitive knee and carry a doctor’s note citing disability laws in Colorado and have never been approached or asked by a ranger or fellow rider about the legality of my bike. That said, I have been using the really quiet and hidden Brose motor and I ride carefully and am friendly with everyone 

I called Geico earlier today. They could insure me with Renters Insurance, but … I would need to have a Renter's Policy first, before the secondary insurance company they deal would insure my two bikes (Surly Long Haul Trucker and Yuba Sweet Curry custom eBike). BUT … unfortunately …. The company that would insure my bicycles will NOT insure me because we have a Pitbull !!! Can you believe that … !!!
For people wanting to push the effects of Statorade to the max, the Australian made Hubsinks can clamp on to your motor shell and provide additional cooling fins to shed heat to ambient air. These fit our new MXUS Cassette motors, and the 9C, Crystalyte H, and many others. These are listed on our new store category for motor cooling mods. And like other small products, we try to  keep a stock of 10mL Statorade syringes on Amazon for easy shipping to US customers. They are sold out now but another shipment is inbound. 
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.
Because the power is applied through the chain and sprocket, power is typically limited to around 250–500 watts to protect against fast wear on the drivetrain. An electric mid-drive combined with an internal gear hub at the back hub may require care due to the lack of a clutch mechanism to soften the shock to the gears at the moment of re-engagement. A continuously variable transmission or a fully automatic internal gear hub may reduce the shocks due to the viscosity of oils used for liquid coupling instead of the mechanical couplings of the conventional internal gear hubs.

If you want an e-bike that positively sprays tech out you, try the Volt Axis on for size. It takes the GoCycle GS's combo of folding, lightweight frame and disk brakes and adds automatic gears, if you please. These react to your speed and pedalling effort. So you automatically gear down when you stop at traffic lights – although what self-respecting cyclist does that? – and then back up as you accelerate.
Today I’m looking at the Rattan Challenger 350W ebike. It can be found for under $680 at Amazon (after Electrek coupon code 5AIDO2GB) shipped and includes free assembly at a local bike shop. I assembled mine at home however in about 15 minutes with the graciously supplied in box hex tool and wrenches. It is pretty straight forward – the hardest part was bolting the front light on.
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!
So first off, it isn’t fair to compare the power of a Chinese rear hub motor watt for watt with a 250W Bosch or Brose or even a Shimano or Yamaha mid-drive motor. There just isn’t even close to the amount of torque or power on a per watt basis and that’s before we get to controllers. However, comparing the Rattan’s 350W motor to the Ancheer’s 250W motor seems more proportionally correct. Where as I could make it about a third of the way up my driveway hill from a cold start on Ancheer throttle, I made it about 2/3rds of the way with the Rattan, or another 100 feet. On a flat surface, again with throttle only, I hit 20 mph in about 10 seconds with the Rattan. It takes me another 5+ seconds to get there on the Ancheer. One note, the battery gauge does bounce around a bit depending on how much it is working. At full throttle you might lose a bar or 2 only to get it back once you coast.

X-Treme is a very well-known distributor of electric scooters and electric bikes with really great customer service. They offer a number of great budget electric bikes, and one of them is Catalina Beach Cruiser. Powered by 500W rear hub motor, this e-bike can conquer almost any terrain. The frame of this bike is 100% hand-welded aluminum, with a step-though design. The top speed on this bike is about 20 mph, with the range of up to 60 miles on pedal-assist mode. The battery pack is 48V LiPo4. This e-bike is an absolute joy to ride. Even more now, with an all new zero resistance rear hub motor with an automatic clutch. This makes riding without power a breeze and you will feel no resistance from the motor. Seat is large and very comfortable, with dual springs for smooth ride. It also comes with a basket, which is a must have if you plan on going for groceries or running errands on this bike.
In general, U.S. and European cycle manufacturers used to assemble cycles from their own frames and components made by other companies, although very large companies (such as Raleigh) used to make almost every part of a bicycle (including bottom brackets, axles, etc.) In recent years, those bicycle makers have greatly changed their methods of production. Now, almost none of them produce their own frames.
Bicycles and horse buggies were the two mainstays of private transportation just prior to the automobile, and the grading of smooth roads in the late 19th century was stimulated by the widespread advertising, production, and use of these devices.[9] More than 1 billion bicycles have been manufactured worldwide as of the early 21st century.[1][2][3] Bicycles are the most common vehicle of any kind in the world, and the most numerous model of any kind of vehicle, whether human-powered or motor vehicle, is the Chinese Flying Pigeon, with numbers exceeding 500 million.[1] The next most numerous vehicle, the Honda Super Cub motorcycle, has more than 60 million units made, while most produced car, the Toyota Corolla, has reached 35 million and counting.[4][5][6][32]
In China, which has the highest number of electric bicycles in the world, electric bikes currently come under the same classification as bicycles and hence don't require a driver's license to operate. Previously it was required that users registered their bike in order to be recovered if stolen, although this has recently been abolished. Due to a recent rise in electric-bicycle-related accidents, caused mostly by inexperienced riders who ride on the wrong side of the road, run red lights, don't use headlights at night etc, the Chinese government plans to change the legal status of illegal bicycles so that vehicles with an unladen weight of 20 kg or more and a top speed of 30kmh or more will require a motorcycle license to operate, while vehicles lighter than 20 kg and slower than 30kmh can be ridden unlicensed. In the southern Chinese cities of Guangzhou, Dongguan and Shenzhen, electric bicycles, like all motorcycles, are banned from certain downtown districts. There are also bans in place in small areas of Shanghai, Hangzhou and Beijing.

The environmental effects involved in recharging the batteries can of course be reduced. The small size of the battery pack on an e-bike, relative to the larger pack used in an electric car, makes them very good candidates for charging via solar power or other renewable energy resources. Sanyo capitalized on this benefit when it set up "solar parking lots", in which e-bike riders can charge their vehicles while parked under photovoltaic panels.[66]
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.
A "class 1 electric bicycle," or "low-speed pedal-assisted electric bicycle," is a bicycle equipped with a motor that provides assistance only when the rider is pedaling, and that ceases to provide assistance when the bicycle reaches the speed of 20 miles per hour. (2) A "class 2 electric bicycle," or "low-speed throttle-assisted electric bicycle," is a bicycle equipped with a motor that may be used exclusively to propel the bicycle, and that is not capable of providing assistance when the bicycle reaches the speed of 20 miles per hour. A "class 3 electric bicycle," or "speed pedal-assisted electric bicycle," is a bicycle equipped with a motor that provides assistance only when the rider is pedaling, (no throttle) and that ceases to provide assistance when the bicycle reaches the speed of 28 miles per hour, and equipped with a speedometer. Local government ordinances are allowed to permit or ban any class of electric bicycles on dedicated bicycle paths and trails, with Class 1 & 2 permitted, and Class 3 banned, by default.
If you are a person who enjoys riding a bike casually at a typical bike path speed (10-15mph), and you like the idea of an ebike push up a hill, against the wind or to relieving a sore knee, then your market for a fully legally defined ebike is very broad and your practical use only has a few limitations. Most ebikes will meet your needs and expectation. I would estimate that 85% of the electric bikes on the market are 100% compliant meeting the federal definition. I encourage you to take the plunge and get a good quality ebike and ride more with assist. Do so with the confidence that electric bikes are here to stay. Coexisting with pedestrians and other cyclist will become a normal part of cycling life.