Maintenance of adequate tire inflation is the most frequent and troublesome concern for cyclists and many means and methods are employed to preserve pneumatic integrity. Thicker tires, thicker tubes, tire liners (of a number of rather impenetrable devices installed between the tire and tube), liquid sealing compounds squeezed into the tube, and automotive-style patch kits are all used to reliably contain the typical tire pressures of 40 to 60 pounds per square inch that are required for bicycle operation. Thin, light bicycle tires are particularly vulnerable to penetration and subsequent deflation caused by goat's heads and other burs, colloquially known as stickers. Inflation of bicycle tires to pressures higher than typical for automotive use requires special pumps. The complexity of bicycle tire maintenance and repair may cause many to not consider the bicycle for transport or leisure.

this bike came really fast. Very surprised at the quality considering the price. It was packaged very well however my fenders had a little kink in it during shipping. I don’t care about that. It is very fast and a solid bike. I own two other Nami electric folding bikes and this is on par with their quality. The only concerns I have is whether or not I’m able to purchase a second battery when this one needs replacement. This is my first electric bike and I’m very impressed with the fun factor.
(15.5) "Electric assisted bicycle" means a device with two or three wheels which has a saddle and fully operative pedals for human propulsion and also has an electric motor. For such a device to be considered an electric assisted bicycle, it shall meet the requirements of the Federal Motor Vehicle Safety Standards, as set forth in 49 C.F.R. Section 571, et seq., and shall operate in such a manner that the electric motor disengages or ceases to function when the brakes are applied. The electric motor in an electric assisted bicycle shall:
Available products (motors, senors, batteries, control systems. etc.) change fast since the e-bike market shows a strong growth. In principle, get a rear motor if you want a lot of raw power and acceleration (e.g. for a 500W motor). Middle motors are more energy efficient and less subject to problems (e.g. overheating). Middle motors usually are combined with integrated rear hub gears, and rear motors with derailleurs. Both have advantages and disadvantages. E.g. the former require less maintenance, are easy to use in go-and-stop traffic, but require taking off weight on pedals when shifting. Therefore the latter (derailleurs) are better for speedy overland and hills cycling.
Many newer or smaller companies only design and market their products; the actual production is done by Asian companies. For example, some 60% of the world's bicycles are now being made in China. Despite this shift in production, as nations such as China and India become more wealthy, their own use of bicycles has declined due to the increasing affordability of cars and motorcycles.[102] One of the major reasons for the proliferation of Chinese-made bicycles in foreign markets is the lower cost of labor in China.[103]
Great bike. Easy to assemble by yourself but if you have a rack let pros do it. No charge for that. Contacted the Addmotor people a few times and they got back quickly even on weekends. Great service. Bike is solid as a rock and excellent components. Only drawback is lack of fenders which I hope someone can manufacture. I would buy again in a nano second!
E-bikes are typically offered in 24V, 36V and 48V configurations. Higher voltage generally means higher top speed – but that may not always be the case. Since the efficiency of a motor and drive system can have an effect on power and speed, a 24V setup could have the same top speed as a 36V setup. Generally you can expect 15-18 mph on a 24v setup, 16-20 mph on a 36V setup and 24-28 mph on a 48V setup. Although it far exceeds Federal laws, some conversion kits can even be run at 72V for speeds of 35+ mph! However, this puts significant stress on bicycle components. Consider that even the fastest athletes only travel 17-18 mph on a conventional bicycle, so 20 mph feels very fast to most riders. Anything over this speed can be unsafe and exceeds law regulations.
Being member of European Economic Area (EEA), Norway implemented the European Union directive 2002/24/EC. This directive defined legal ebikes for all EU and EEA countries to "Cycles with pedal assistance which are equipped with an auxiliary electric motor having a maximum continuous rated power of 0.25 kW, of which the output is progressively reduced and finally cut off as the vehicle reaches a speed of 25 km/h or if the cyclist stops pedaling.” The definition became part of Norwegian vehicle legislation[17] in 2003. A more detailed specification will become effective when the new European ebike product safety standard EN 15194 is published in 2009.
Legislative changes in 2012 significantly altered the classification and regulatory structure for e-bikes. The general effect was to establish electric-assisted bicycles as a subset of bicycles and regulate e-bikes in roughly the same manner as bicycles instead of other motorized devices with two (or three) wheels. Laws 2012, ch. 287, art. 3, §§ 15-17, 21, 23-26, 30, 32-33, and 41. The 2012 Legislature also modified and clarified regulation of e-bikes on bike paths and trails. Laws 2012, ch. 287, art. 4, §§ 1-4, 20.
I eventually got used to it over time, but at first having both kids behind me made the bike feel like it would sway to or fro perilously. I think it was just too much weight to navigate safely, and would be fine with younger kids that didn’t come close to the 120-pound weight limit for the rear cargo area. Overall I’m still a bit partial to a box-style bike if I’m hauling multiple kids and want to be able to see what they’re doing.
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.
5. Prizes: The approximate retail value of all prizes is $1361. The prizes are: Performance E-BikeKit or Heavy Duty E-BikeKit. You are not guaranteed to win a prize and your chance of winning is dependent on the total number of eligible entries received. Actual/appraised value may differ at time of prize award. The specifics of the prize shall be solely determined by the Sponsor. No cash or other prize substitution permitted except at Sponsor's discretion. The prize is nontransferable. Any and all prize related expenses, including without limitation any and all federal, state, and local taxes shall be the sole responsibility of the winner. No substitution of prize or transfer/assignment of prize to others or request for the cash equivalent by winners is permitted. Acceptance of prize constitutes permission for Electric Bike Technologies INC. to use winner's name, likeness, and entry for purposes of advertising and trade without further compensation, unless prohibited by law.
None of this would matter if the VanMoof Electrified S2 (and its close relative the X2) wasn't fun to ride, but it is a blast. Like the Brompton, it pulls off the neat trick of powering you along but giving the illusion that you're doing the work, reacting quickly and cleverly to the speed of your pedalling and the difficulty of any incline you're on.