How Do Electric Bikes Work

Electric bikes, or e-bikes, are one of the fastest-growing segments in the bicycle industry. They’re also a great way to get from point A to point B fairly quickly and efficiently. But how does an electric bike work?

What is an Electric Bike?

In a nutshell, an e-bike is a bicycle that is powered by an electric motor. The motor provides assistance to the rider while they are pedaling, making it easier to ride the bike up hills or over long distances.

What Are the Main Components of an E-Bike?


The battery is the power source of an electric bike. It provides the power needed to run the electric motor and it is usually one of the most expensive components. The most common type of battery used for electric bikes is Lithium-ion (Li-ion), which is known for its high energy density, long life cycle, and low self-discharge rate.

The battery capacity is measured in Watt-hours (Wh) and it ranges from 250Wh to over 1000Wh. The larger the battery capacity, the longer the bike can run without recharging. The battery is usually mounted on the frame or rear rack of the bike and it can be easily removed for charging.

Electric Motor

The electric motor is the component that converts electrical energy into mechanical energy, and it is what makes the bike move.

There are two types of electric motors used in e-bikes: hub motors and mid-drive motors. Hub motors are located in the hub of the wheel and they directly drive the wheel, while mid-drive motors are located in the center of the bike and they drive the chain.

The e-bike motor provides power assistance to the rider and it is controlled by the controller. The motor power is measured in Watts and it ranges from 250W to over 750W. A higher motor power means a faster and more powerful bike, but it also means higher energy consumption and shorter range.


The controller is the component that regulates the flow of electrical power from the battery to the electric motor. It acts like a “brain” for the electric bike and it controls the amount of power that is delivered to the motor based on the rider’s input.

The controller also manages the charging of the battery and it protects the battery and motor from overloading or overheating. The controller is usually located near the motor or in the battery housing.

Pedal Assist Sensor

The pedal assist sensor also referred to as the electric assist is a device that measures the rider’s pedaling effort and provides power assistance accordingly.

The rider can adjust the level of assistance to their liking, from low to high. When the rider starts pedaling, the sensor detects the movement and sends a signal to the controller, which then delivers the power to the motor.

The pedal assist sensor helps the rider to achieve a natural and efficient ride experience, and it also extends the range of the bike.


The throttle is a device that allows the rider to control the speed of the bike without pedaling. It can be used as an alternative to the pedal assist sensor, or in combination with it.

The throttle can be a twist grip or a thumb lever, and it is usually located on the handlebar. The throttle provides the rider with full control over the speed and power of the bike, and it is particularly useful for starting, accelerating, and climbing hills.

What Is the Working Principle of an E-Bike?

Now that we have already covered the main components of an e-bike, let's discuss how it works to provide a smooth and efficient ride.

When the rider begins to pedal, the motor receives a signal from the battery-powered control unit that it should start providing assistance. The control unit determines the amount of assistance based on factors such as the rider's speed, the level of pedal assist selected, and the amount of torque applied to the pedals.

The rider can select the level of pedal assist through a control panel or a handlebar-mounted display. The higher the level, the more power the motor will provide.

At the same time, the speed sensor detects the speed of the bike and the torque sensor detects the amount of force applied to the pedals. This information is then communicated to the control unit, which uses it to adjust the amount of assistance provided by the motor.

The electric motor is powered by a rechargeable lithium-ion battery, which provides the energy needed to assist the rider. It is connected to the pedals through a system of gears and chains, which transmit the power from the motor to the wheels.

The power controller regulates the flow of current from the battery to the motor, ensuring that the motor is supplied with the right amount of power to provide the desired level of assistance.

The controller also monitors the battery voltage and will cut off power to the motor if it drops below a certain level. This feature prevents the battery from running out when you’re on a long ride.

Most e-bikes also have a throttle that allows you to control the speed of the bike without pedaling. This is especially useful when riding on hilly terrain since it can help you maintain your speed when going up hills.

What Is the Range of an Electric Bike?

The range of an e-bike is the distance it can travel on a single charge of its battery. The range of an e-bike can vary greatly depending on several factors, including the battery capacity, the rider's weight, and the terrain.

On average, electric bike batteries can last anywhere from 20 to 80 miles on a single charge. However, this can vary widely depending on the specific model and how it is used.

For example, an electric bike with a large battery capacity and high level of pedal-assist can travel up to 100 miles or more on a single charge, while an e-bike with a smaller battery and lower level of pedal-assist may only travel 30 miles or less.

The rider's weight can also have an impact on the range of an e-bike, as a heavier rider will require more energy to move the bike.

The terrain also plays a role, as riding on hills or rough terrain will require more energy than riding on flat surfaces.

How Do You Calculate the Range of an Electric Bike?

The range of an e-bike can be calculated in several ways. You can calculate the range based on the amount of electricity stored in the battery, or based on how far you can travel with a fully charged battery.

The first method is easier to calculate, but it doesn’t account for how fast the battery is drained or how much power you use on a ride. The second method is more accurate, but it requires some math.

Here were are only going to cover the first method.

First Method

The range of an electric bike is calculated by multiplying the amps of your battery by its voltage. The wattage (watts) you get from this calculation is how much power your battery can deliver at any given time.

If we take an example of a 24V (volts) 10Ah(amp hours) lithium-ion battery, this would be equal to 240Wh (Watt Hours). This means that if you were to use all 10Ah from this battery at once, it would provide 2.4kW for 1 hour before being drained completely - meaning your range would be as follows:

4 x 10 = 24kW or 24000 watts;
24000 / 1000 = 24 miles of range.

What Are the Advantages of E-Bikes?

Increased Efficiency

One of the biggest advantages of e-bikes is that they provide a more efficient mode of transportation than traditional bikes. With the help of an electric motor, riders can cover more ground in less time and with less effort, making e-bikes an attractive option for commuters and recreational riders alike.

The motor can be set to various levels of assistance, allowing riders to customize the level of effort required to operate the bike. This makes it easier for riders to tackle hills, headwinds, and other obstacles that would normally slow them down or require more effort to overcome.

Reduced Physical Effort

E-bikes are also a great option for riders who are looking to reduce the physical effort required to ride a traditional bike. With the assistance of the motor, riders can conserve energy and reduce fatigue, making it easier to cover longer distances and complete longer rides. This makes e-bikes a popular choice for people who want to stay active but may not have the physical ability to tackle challenging terrain on a traditional bike.

Environmentally Friendly

E-bikes are a much more environmentally friendly option than cars or motorcycles. They produce no emissions, making them a clean and green mode of transportation. Additionally, e-bikes can be powered by renewable energy sources, such as solar panels, reducing the carbon footprint of the bike even further. This makes e-bikes a great option for riders who are concerned about the environment and want to reduce their impact on the planet.


Another advantage of e-bikes is that they can be more cost-effective than traditional bikes or cars. With the assistance of the electric motor, riders can cover more ground with less effort, making it possible to use the bike for commuting, errands, and other short trips. This can save riders money on fuel costs and maintenance, making e-bikes a cost-effective option for transportation. Additionally, e-bikes typically have lower operating costs than cars or motorcyles as they require less maintenance and have a longer lifespan.

Limitations of Electric Bikes

Battery Life and Range

One of the major limitations of electric bikes is their battery life and range. The distance that an electric bike can travel on a single charge is known as its range. The range of an electric bike is determined by several factors such as the size of the battery, the efficiency of the motor, and the weight of the rider.

In general, electric bikes can have a range of anywhere between 40 to 100 miles on a single charge, depending on the make and model. However, the range can be reduced if the bike is ridden at high speeds, in hilly terrain, or if the rider is carrying a heavy load.


Electric bikes are relatively expensive compared to traditional bikes, due to the cost of the battery, motor, and other components. The cost of electric bikes can vary significantly, depending on the quality and features.

Weight and Portability

E-bikes are heavier than traditional bikes due to the weight of the battery and motor. This can make it difficult to transport the bike and can also affect the handling and performance of the bike.

Some electric bikes come with removable batteries that make them more portable, but this can also add to the cost of the bike.

High Maintenance

Some of the reasons why e-bikes can be considered high maintenance include:

  • Battery maintenance: The battery is one of the most critical components of an electric bike, and it requires routine maintenance to ensure that it continues to function efficiently.
  • Motor maintenance: The motor in an electric bike is subject to wear and tear, and it may need to be serviced or replaced if it fails. The frequency of maintenance required will depend on the quality of the motor, the amount of use, and the conditions in which it is used.
  • Drivetrain maintenance: The drivetrain of an electric bike, which includes the chain, gears, and sprockets, requires regular cleaning and lubrication to ensure that it functions smoothly. Over time, the chain may stretch, and the gears may wear, which will require replacement.
  • Tyre maintenance: The tyres on an electric bike need to be regularly checked for wear and replaced when they become worn. Tyres that are under-inflated or worn can affect the performance of the bike and make it more difficult to control.
  • Regular cleaning: Electric bikes can get dirty and covered in mud, especially if they are used for off-road riding. This can affect the performance of the bike, and it may be necessary to clean it regularly to ensure that it continues to function properly.

Legal Restrictions

Electric bikes are subject to legal restrictions in some countries and regions. In some jurisdictions, electric bikes are restricted to certain speeds or are not allowed on certain roads or trails. In others, electric bikes may require registration, licensing, and insurance.

It's important to be aware of the local laws and regulations before using an electric bike.

Final Thoughts

E-bikes have emerged as a popular alternative mode of transportation in recent years. With their electric motors, they offer a convenient and eco-friendly way to cover long distances without much effort. Additionally, e-bikes also provide a great workout option for people who want to cycle without putting too much strain on their bodies.

As battery technology improves, e-bikes are becoming more affordable and accessible to a wider audience. They offer a practical solution for commuting, errands, and recreation.

E-bikes are not only reducing carbon footprint but also promoting a healthier lifestyle. The future of transportation looks bright for e-bikes as more and more cities are investing in bike-friendly infrastructure and policies.

Ebike guide