|How Far Can it Go?
The manufacturers published range on an electric bike can be misleading. Range is usually a function of battery capacity and motor power, though the range of your electric bicycle can vary significantly based on how and where you are riding.
All battery packs on bicycles are rated in Amp-Hours (Ah). Ah is a number that represents the capacity of the battery—how many gallons are in the tank, so to speak. It is important to note that the voltage of the battery can also help increase the range. Switching from a 26-volt to a 37-volt battery can bring gains of nearly 30% in range.
Significant gains in range also come from using the pedals and gearing of the bike as much as possible. Even in situations when you do not need to pedal, using the bicycles transmission, shifting gears, and adding your human power helps keep battery power in reserve for when you really need it. Some power assist bicycles have multi-mode assist settings that vary the total motor output based on a preset assist level. Some manufacturers publish a range based on the lowest assist setting—sometimes as low at 10%!
Finally, when choosing an electric bike it is critical to understand that there is a zero sum relationship between speed, range, and weight. This means that higher assist speeds and long range require much larger batteries and a heavier bike. Conversely, a lighter bike will have a lower speed, or range. The best manufacturers have built their bikes with a good balance between speed, weight, and range.