Put the wheel with the electric hub on your bike and connect the brake components. Simply reverse the process you used to remove the wheel in order to reinstall it. Be sure to adjust the chain so it fits properly if you’re replacing the back wheel. If the bike has rim or cantilever brakes, simply close them over the new wheel using the lever. If the bike has disc brakes, put the pads back in place and secure them using the clips, springs, or cotter or retaining pin.
Under the doctrine of One Country, Two Systems, Hong Kong has independent traffic law from mainland China. Electric bike are considered as motorcycles in Hong Kong, and therefore needs type approval from the Transport Department as other automobiles. All electric bike availble in Hong Kong fail to meet the type approval requirement, and Transport Department has never granted any type approval for electric bike, making all electric bike effectively illegal in Hong Kong. Even if they got type approved, the driver would need a motorcycle driving license to ride. As a side note, Hong Kong doesn't have a moped vehicle class (and therefore moped driving license), and mopeds are consided as motorcycles too.
Electric bicycle fits under the definition of "moped" under Kentucky law. You don't need tag or insurance, but you need a driver's license. "Moped" means either a motorized bicycle whose frame design may include one (1) or more horizontal crossbars supporting a fuel tank so long as it also has pedals, or a motorized bicycle with a step-through type frame which may or may not have pedals rated no more than two (2) brake horsepower, a cylinder capacity not exceeding fifty (50) cubic centimeters, an automatic transmission not requiring clutching or shifting by the operator after the drive system is engaged, and capable of a maximum speed of not more than thirty (30) miles per hour Helmets are required.
A new electric cyclist will likely experience two conflicts of thought: 1). Will the general public accept my use of this power assist technology, or Will they ridicule and reject me as being lazy? 2). Will I stand out to law enforcement by the look of my bike or riding a bit faster than other cyclist on hills and roads? Grappling with these two thoughts will tempt most folks to try and remain unnoticed and ride more responsibly. After I became an advocate of e-transportation on two wheels, enjoying the benefits of power assist commuting, I eventually was a bit put off by this federal law, especially the 20mph limitation. Is 20 mph really practical and justified? Is it not true that many active young people on typical road bicycles are able to actively ride in the 20-25mph range? I discovered that ebikes, with larger tires and disk brakes, can comfortably and safety cruise in that range of speed. The standard 2001 Federal law of 20mph, eventually became a practical limitation for an ebike commuter of over 20 miles a day, and caused me to get a bike beyond the federal limits, making me more alert and sensitive when riding in the presence of the police.
Photo: Zap Electric's power-assist kit turns a conventional bike into an electric one. There's a bolt-on DC electric motor (weighing just over 3kg or 7lb) just above the back wheel, behind the police officer's foot, pressing against the tire and driving it by simple friction. The motor's powered by a compact lead-acid battery (weighing about 5.5 kg or 12 lb) inside a protective nylon bag. This kit adds quite bit of weight to the bike, but gives extra range and speed when needed. Photo taken in Santa Rosa, California by Rick Tang courtesy of US DOE/NREL.
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.