Chapter 3: How do Electric Bikes Work?

So now that you understand the benefits of electric bikes and why millions of people worldwide are riding them, it’s good to understand how electric bikes work. This will help you make a more informed decision when you go to purchase an electric bike.

There are three main types of electric bikes:

  • Pedal Assist
  • Power On Demand
  • Speed Pedelecs

Pedal Assist

Pedal Assist electric bikes, sometimes referred to as “pedelecs,” are equipped with electric motors that provide additional power when the bike is being pedaled. They are considered “class 1 e-bikes” in the United States. A sensor detects when the bike is being used, and provides the selected level of assistance. Some people explain the experience like having an invisible hand pushing them as they ride.

Most pedal assist electric bicycles allow the rider to tailor the bike’s power to meet specific physical needs and geographies. For instance, if you know if there is a big hill on your route, you may want to increase the power so you have additional assistance while pedaling.  

Pedal assist electric bicycles are a great for all around use, since they allow riders to adjust how much or how little assistance they need at any given time.

Power on Demand

The primary difference between pedal assist electric bikes and power on demand electric bikes is that power on demand bikes allow for manual control of the electric motor manually. Similar to operating the power on a moped or motorcycle, riders can activate the motor with a throttle, button or trigger located on the handlebar. Just as a pedal assist electric bike, power on demand electric bicycles are limited to a maximum of 20 mph and 750 watt motors, although most electric bike motors are between 350 and 500 watts. Power on Demand e-bikes are considered class 2 ebikes in the United States.

Some power on demand electric bikes have a throttle function only, but typically power on demand ebikes let the rider take advantage of both pedal assist and a manual throttle when needed.

Power on demand bikes are also great for people who may want to switch between a physically strenuous bike ride one day, and an easy commute with less sweat another day or not even pedal at all sometimes. It’s also very useful if you want to avoid the first two or three pedal strokes after a stop, and get the speed up with help from the throttle.

Speed Pedelecs
Speed pedelecs, which are sometimes called “s-pedelecs,” are the fastest street legal ebikes that do not require licensing, and they provide the greatest amount of power. Speed Pedelecs have a maximum speed of 28mph and are considered class 3 electric bikes in the United States.

If considering an s-pedelec, you should check the laws in your specific location, since some jurisdictions limit the use of these electric bikes. For example, they may not feature a throttle in the state of California, where they may be used in bike lanes but not on bike paths. Some jurisdictions may require a special registration and driver’s license, prescribe age limits and helmet requirements, and restrict certain riding areas

Electric bikes with power over 750W and/or top speeds above 28mph are considered class 4 ebikes, which fall under the same jurisdiction as electric mopeds and motorcycles and are subject to licensing and registration requirements of motor vehicles.