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.
Power assisted bicycles are classified in two categories in Saskatchewan. An electric assist bicycle is a 2 or 3 wheeled bicycle (sic.: 3 wheeled bicycle) that uses pedals and a motor at the same time only. A power cycle uses either pedals and motor or motor only. Both must have engines with 500 watt power or less, and must not be able exceed 32 km/h (20 mph), i.e., electric motor cuts out at this speed or cycle is unable to go this fast on a level surface. The power cycle has to meet the Federal Motor Vehicle Safety Standards for a power-assisted bicycle. The power cycle requires at least a learner's driving licence (class 7), and all of the other classes 1-5 may operate these also. The electric assist bicycle does not require a licence. Helmets are required for both. Both are treated as bicycles regarding rules of the road. Gas powered or assisted bicycles are classified as motorcycles regardless of engine size or if using pedals plus motor. Stickers identifying the bicycle's compliance with the Federal classification may be required for power cycles by some cities or municipalities. 
I would advocate you ride legal within the laws of your state. I would also look into some kind of liability rider or umbrella policy with your home owner’s policy, which covers your personal liability and theft. Get your bike registered; wear your helmet, eye protection, whatever is required by state law so that if an accident occurs and you are at fault, there is no legal recourse. Even if you own a 750W/20mph ebike that meets the definition of a bicycle, any at-fault cyclist may still be denied coverage by stingy insurance companies who want to support their clients. Your health insurance will usually cover your medical bills, but the costs of an expensive ebike may be lost.
My homeowners (State Farm) covers bikes , but assumes $500 per bike. They will add the bikes as personal property, but the premium is excessive (about $300/year per bike, and we have four bikes). I did increase our personal umbrella liability coverage, and it covers us if family members any sort of accident on our e-bikes that injures us or others or others' property, though only covers $500 each for our own bikes (under the homeowners coverage). It was not very expensive to increase the umbrella policy (as it resulted also in a reduced rate on our car insurance).
In the year 1885, a British man named J.K. Stanley introduced what can fairly be described as the first modern bicycle. His Rover bike had wheels of equal size in the front and back and used a chain connecting the pedals and the rear wheel as a propulsion system. It was often marketed as a safety bike in contrast with the unstable Penny Farthing, and was a smashing success. The company went on to develop motorcycles and automobiles, remaining in business until the year 2005.
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:
If you're taking your bike inside, consider one that folds up. The Cyclotricity Wallet has a motor in the front wheel, which takes you up to speed either by assisting your pedalling, or you can sit back and use the throttle by itself. Its folding design makes it slightly easier to get in and out of a building, but its hefty weight means you still won't find it easy to carry onto public transport.
Under the Guide Section of EBR, Court has written a full article, dedicated to the new classification approach, which was initiated by the BPSA (Bicycle Product Suppliers Association), supported by PeopleForBikes, and then Calbikes. The initiative was meant to be pro-active with ebike legislation, to establish self-imposed, measurable, distinct classes of electric bikes before states start hearing about anecdotal problems and potentially overreact to the technology with wide sweeping limitations.
Great question… a real world situation from someone doing their best to follow the law but also be realistic about time/distance. What follows is my opinion on the matter based on lots of electric bike riding experience, this is not legal advice. You can probably ride with electric assist across the dirt way with no issues and avoid any negative response that might arise as long as you’re polite to other cyclists and pedestrians and pedal along without going too fast. If someone called you out about it you could easily hop off, walk your bike and explain that you use the assist to help make your commute possible or possibly, like me, you have a knee injury and it’s difficult to pedal through softer terrain like gravel. Another different approach might be to shut the bike off completely before entering the gravel section, you could even take the battery off and put it in a backpack or as mentioned earlier… just walk the bike. Imagine if you had a motorized dirt bike and were just pushing it along a sidewalk… this kind of vehicle definitely is not allowed on sidewalks or most gravel paths like the one you’re describing but if you were escorting it carefully, you’d be honoring the spirit of the law and if an officer or pedestrian jumped out and started questioning you about your “motorized vehicle” it is my feeling that a genuine explanation and apology or request for guidance would go very well. I personally have never had issues riding electric bikes in part because I am thoughtful about how I use them. I do occasionally switch them off and sometimes I get off and walk. I have asked police in many cities across the US what they thought about ebikes and in every case I have received positive interest and support with guidance to ride safe with a helmet and follow traffic laws in the street. I hope this helps and I wish you well, it’s nice that you care enough to ask and I hope you’re treated well by others out on the road. The flip side of this response is that I have been harassed, yelled at and even swerved at by automobiles when riding bicycles and electric bikes. This usually happens in the evening after work lets out when traffic is heavy and I’m riding on the shoulder or in the street (where marked to do so) and I believe it has to do with territory, testosterone and socio-economic standing more so than laws or anything like that.
The Christmas day is coming soon, since I receive the bike, it's about a week, and I am satisfied with it! just as advertised, very powerful and good design. the most important point is that once the battery is FULL CHARGE, how far it can reach up to. I have a funny test, in the normal road(not in the dramatic slope or uphill), it can goes almost 44 miles. That is what I give 5 star for this bike! very powerful with reasonable price!
Several bills have been sponsored to legalize electric bicycles for use on NYS roads, and several have overwhelmingly passed at the committee level, but none of these initiatives has been able to be heard and then passed in the New York State Senate, until 2015. The latest bill S3997, "An act to amend the vehicle and traffic law, in relation to the definition of electric assisted bicycle. Clarifying the vehicle and traffic law to define electric assisted bicycles; establish that electric assisted bicycles, as defined, are bicycles, not motor vehicles; and establish safety and operational criteria for their use." has passed in the Senate for the first time ever in 2015. The related Assembly bill A233 was not brought to a vote in the assembly even though it had passed with little issue in prior years.
Alberta identifies e-bikes as "power bicycles" and is consistent with the federal definition of "power-assisted bicycle" in MVSR CRC, c 1038 s 2. Motor output must not exceed 500 W (0.671 hp) and e-bikes cannot travel faster than 32 km/h (20 mph). Fully operable pedals are required. No driver's license, vehicle insurance, or vehicle registration is required. Operators must be 12 years of age or older. All operators are required to wear a motorcycle helmet meeting the standards set in AR 122/2009 s 112(2). A passenger is permitted only if the e-bike is equipped with a seat designated for that passenger.
However, Emu sells a little foldable number if that's your bag. The Emu Crossbar is for town commuters that require a sweet ride that's backed up by solid Shimano Nexus hub gears and Tektro brakes, which are adequate if not the best on the market. Riding is smooth and easy, with the crank moving sensor doing its best to iron out any gaps in power delivery.
An anti-theft radio GPS that mounts to standard bottle cage bosses and can locate within 9 feet, it runs on the Verizon network and costs $5/mo in addition to the hardware. Integrated vibration sensing alarm sends an automated text message alerting you anytime the bike has been "locked" using the companion smartphone application (Android or iOS)...