Electric bikes, or ebikes, are bicycles that have an electric motor and a battery to assist the rider. They can make cycling easier, faster, and more fun, especially on hills or long distances.
But how do electric bikes work? Generally, electric bikes are easy to use, ride, and keep. They need little maintenance besides what a normal bike needs.
In this blog post, we will explain what electric bikes are, the main components of an e-bike, and how these components work together.
We will also discuss what are wattage, voltage, and amp-hours. Why these factors are so important, and how they affect the operation of electric bikes.
What is an Electric Bike?
An electric bike is not the same as a scooter or an electric motorcycle because they have a distinct appearance.
Imagine a normal bike, but with some extra parts like a battery, a motor, and a controller that are all blended into the shape. These are the basic elements of every electric bike that you can find!
How Do Electric Bikes Work?
An electric bike feels and rides like a normal bike. It mostly has the same components as well.
The electric part is designed to enhance human power, not to take over it. It helps you overcome challenges like slopes and wind and lets you go longer distances with less fatigue.
An electric bike has a motor that helps the rider pedal with less effort. Some models can run on the motor alone, while others need some pedaling from the rider.
Electric bikes are not the same as motorcycles. They have a shorter battery life and a lower speed than gas-powered bikes. But they are more eco-friendly and healthy, as they do not emit harmful gasses and still require some physical activity from the rider.
Electric bikes are not unlimited in their speed, even with a motor. The 2002 Consumer Product Safety Act sets the rules for what counts as a low-speed electric bike.
The maximum speed you can reach with the motor depends on the type of bike you have. It can range from 20 to 28 miles per hour (mph).
There are three classes of electric bikes in the states that have laws about them. You should check your state laws before you ride, as some classes may have age restrictions.
Class 1: These bikes help the rider pedal up to 20 mph. Read more
Class 2: These bikes can move on the motor alone up to 20 mph. Read more
Class 3: These bikes are the fastest and help the rider pedal up to 28 mph. Read more
Components of Electric Bike
The battery, the motor, the controller, and the sensor are the four main components that differentiate electric bikes from standard bicycles.
The Battery
The battery is a key factor in determining the bike’s weight, style, and range. It is essential to understand how electric bikes work and what types of batteries are available. Most of the batteries on the market belong to one of these two groups:
Sealed Lead Acid (SLA)
This was the common battery type for electric scooters and bikes in the past. Nowadays, most electric scooters still use SLA batteries, but electric bikes (which often need human power) have switched to newer battery technologies to reduce the bike’s weight.
Advantages
- Cheap
Disadvantages
- Heavy and large
- Have a shorter travel distance
- Last for only about 100-300 full cycle charges
- Need more care, and must be charged right after use
Lithium (Ion/Polymer/Manganese)
These are the latest technology in batteries. A lithium battery has a lifespan about 2-3 times longer than an SLA battery. Lithium batteries are much lighter and also require little maintenance.
Advantages
- Lightweight – high-capacity, 36V 10Ah Lithium-Polymer batteries can be as light as 6 pounds!
- Have a longer travel distance – battery can go up to 40 miles in pedal-assist mode (or 20 miles on throttle-only).
- Last for about 800 charges or 3 years of regular use
Disadvantages
- More costly – starting from about $500 to $1,500 and above
The Sensor
The sensor on an electric bike is a vital part. It can be one of two kinds of sensor on different e-bikes; a cadence sensor or a torque sensor.
The cadence sensor activates the motor as soon as you start pedaling which gives you the riding support.
The torque sensor is more intelligent. It gives you a little bit of support to match your speed when you are in motion. It’s more agile and helps with speed and movements.
To stop electric bikes from going too quickly, they have sensors that check your speed to decide when to tell the motor to switch the throttle or pedal assist on or off.
The sensors can measure speed or torque. Both work similarly, though. The speed sensor tracks how fast you go. A torque sensor, on the other hand, checks how hard you pedal, as harder pedaling means faster speeds.
The Controller
The controller is a crucial part of how electric bikes work and lets you control the electric support on your electric bike. The controller is on the handlebar for convenience.
There are two main kinds of controllers – pedal-activated and throttle-based controllers.
Pedal-activated systems give you electric support as you pedal down. You don’t need to use a throttle – just pedaling will work.
Electric bikes with pedal-activated systems have a controller on the handlebar that lets you change the level of support that you get as you pedal. You can choose the amount of support you want, from no support to a lot of support.
Throttle-based controllers use a simple throttle device. The throttle can be either a twist-grip type or a thumb-press type.
With a throttle, you just pull back or press the throttle to get the electric support. Some electric bikes only need you to turn on the throttle, letting you ride without pedaling.
The Motor
Electric bikes have motors with different power ratings, ranging from 200W to over 1000W. In the US, the maximum allowed is 750W, but some states may have lower limits.
This limit is similar to horsepower. A higher rating means that the bike can carry more weight more easily – but it also uses more battery power while doing so. As a result, a 750W motor will use up the battery faster than a 250W one, but it will be stronger.
However, there is another factor to consider. The way and place the motor is built affects how electric bikes work.
The most common type of motor for electric bikes is a hub motor. It is usually part of the back or front wheel. When it is on, it drags or pushes the wheel forward.
This system works fine, but it has a major drawback. Since it is not linked to the bike’s gears, it is less efficient on hills and uneven terrain.
Imagine driving a car in only one gear all day. It will take you places, but it won’t give you the best amount of torque or speed that you get with a full gear range.
Some e-bikes have a mid-drive motor, which is connected to the crank and the gears. Mid-drive motors have several benefits:
- The bike works better and uses less battery, because the mid-drive motor uses the bike’s gears.
- The bike can climb hills better, because you can switch gears depending on how steep the hill is.
- The bike is easier to control, because the motor is near the ground and the weight is even and low.
How Electric Bike Motors Work?
Electric bikes use a motor to enhance your riding ability. If you get tired while riding an e-bike, you can use the throttle to help you move.
Pedal-assist also helps you while you pedal the bike, making you use less energy. But the pedal-assist stops when you stop pedaling or exceed the preset speed limit of the bike.
The motor converts electrical energy into mechanical work that it uses to help spin the bicycle’s wheels. Manufacturers have three places for putting the motor — the front hub, rear hub and in the middle of the bike.
Motors put on the front hub are less common today than those put in other places on the bike. You will usually find these front-put motors on low-end e-bikes.
Rear-hub motors power the bike from the rear wheel and work with the bicycle gears. The motor in this place improves grip and handling because of its link to the gearing. With better control, rear hub motors often show up on mid-class e-bikes.
Premium, and very pricey, electric bikes have their motors close to the center of gravity and fixed to the frame. This motor place does not stop you from quickly changing tires on your bike while making the bike steady.
E-bikes are usually made with electronic parts that have safe coverings with tight seals to prevent damage from light rain.
They can handle a variety of climates, but it’s important to be sensible and avoid exposing an e-bike to too much water and/or rain.
Now that you know about the parts that make an e-bike different from a normal bicycle, learn more about the power options and what they mean.
What is Electric Bike Wattage?
Your bike’s battery power depends on three factors: wattage, voltage, and amp-hours. The wattage tells you how fast and powerful your bike can be.
To know how long your bike can run on a single charge, you need to learn the differences between wattage and watt-hours.
What is Wattage?
The power output of a motor is called wattage. You can find the wattage of the motor power as two numbers: peak and nominal power. These numbers show the best possible value and the usual working value of the motor.
The peak power is the maximum power that the motor can give under perfect conditions and full speed. But you will not get this power all the time because some power is wasted by friction and other factors.
The nominal wattage is the realistic power that the motor can give. It is usually 75% of the peak power at the highest levels. This is the first number that you see with the motor power and it shows the actual performance. You need this number to find out the watt-hours.
The watt-hours tell you how long you can ride your bike with its motor before you have to charge it again. They also tell you how fast your e-bike can go.
The Importance of Wattage for Electric Bikes
The watt-hours of your bike depend on the motor power wattage. You need a bigger battery for motors with higher watts because they use more power.
You get the watts by multiplying the battery’s voltage and the motor controller’s amps. For example, a bike with a 52-volt battery and 20-amp controller has a calculated wattage of 1,040 watts.
52 volts × 20 amps = 1,040 watts calculated power
The nominal motor wattage is the realistic power that the motor gives. You get it by multiplying the calculated wattage by 0.75 or 75%.
1,040 × 0.75 = 780 watts nominal power
You get the watt-hours by multiplying the battery’s voltage and its amp-hours. For example, a 52-volt battery with 13 amp-hours has 676 watt-hours of power.
52 volts × 13 amp-hours = 676 watt-hours
To find out how long your bike’s battery can run at full speed, divide the watt-hours by the nominal motor wattage. For the example above, divide 676 watt-hours by 780 nominal watts.
676 ÷ 780 = 0.867 hours
Multiply this number by 60 to see how many minutes the battery can run.
0.867 hours × 60 minutes = 52 minutes
This number shows how long the battery can run at full speed without stopping. You can make the battery last longer by pedaling more and using the motor less.
There are many other things that change how far and how long you can ride your bike, such as how much weight you carry, how fast you go, how much air is in your tires, and more.
Remember, e-bikes are meant to help you bike better, not to do all the work for you.
What is Electric Bike Voltage?
The bike’s battery determines the voltage for your electric bike. You can get much more voltage from lithium batteries than from the old lead-acid ones.
What is Voltage?
The voltage of the battery indicates how much power it can deliver to your bike’s motor. The higher the voltage, the faster the power can flow from the battery to the motor, improving performance.
The voltage, along with the amp-hours, tells you the watt potential of the battery.
The battery will have the voltage written on it. Some of the best bikes have batteries with 48 or 52 volts. You can use a battery with a higher voltage than your bike needs to enhance the performance.
Most bike motors can handle a certain amount of extra voltage before they get damaged.
Some bikes have motors that can work with batteries with lower voltages. For example, the RipCurrent S bike can use either a 48-volt battery or a 52-volt one. Not all brands have this feature to use batteries with lower voltages on bikes with higher voltages.
Right now, 52 volts is the maximum for electric bike batteries. Higher voltages are unlikely to be used on existing electric bike models because they would be considered high-voltage and need more regulations.
The Effect of Voltage on E-Bike Performance
Your e-bike has a voltage limit that you should follow when picking your battery. A higher battery voltage can make your bike perform better.
Batteries with higher voltages are more efficient, which is why they can enhance your bike’s performance. These batteries use less current to provide the same power as batteries with lower voltages. Because they work less, they have more efficiency and a longer battery life.
Batteries with higher voltages can give your bike the extra boost it needs to go up hills or carry heavier people or loads. It does this by sending the electricity from the battery to the motor quicker than batteries with lower voltages.
What Are Electric Bike Amp-Hours?
Your e-bike has a voltage limit that you should follow when picking your battery. A higher battery voltage can make your bike perform better.
Batteries with higher voltages are more efficient, which is why they can enhance your bike’s performance. These batteries use less current to provide the same power as batteries with lower voltages. Because they work less, they have more efficiency and a longer battery life.
What are Amp-Hours on a Battery?
The amp-hours of your battery tell you how long the battery can run before charging. For instance, a 20 amp-hour battery can run for 20 hours with one amp of power. If your motor uses more power, the battery will run out faster. With two amps per hour, the battery will run for 10 hours.
You can compare amp-hours to the gas tank and amps to the gas. More amp-hours mean longer running time with the same bike use and power consumption.
How Amp-Hours Affect the Performance of E-Bikes
The amp-hours and the battery voltage are both important factors in determining how long you can ride your electric bike on one charge. As mentioned, the watt-hours are the result of multiplying these two.
The amp-hours are like the gas tank, the amps are like the gas and the volts are like the gas flow. These factors help you to estimate how long the charge will last at full capacity, which is the watt-hours.
Without knowing the amps or amp-hours of your bike’s battery, it would be hard to compare different models. Amps also help you to choose the best charger for your bike.
The battery and the charger will have the amps written on them. Higher amps on the charger will make your bike charge faster. The amps on the charger show how many amps the charger will transfer per hour to the battery.
For instance, a normal two-amp charger puts two amps of power into the battery each hour. It would take 5.2 hours to charge a 13 amp battery from 10% to 90%.
If you swapped the normal charger for a super-fast one that transfers seven amps per hour, the charging time would be 1.5 hours.
How Electric Bike Components Work Together?
Electric bikes are similar to regular bikes, but they have some extra components that work together to provide electric assistance. The role of each component is:
Motor
The motor is the source of power for the e-bike. It can be located in the hub of the front or rear wheel, or in the middle of the frame. The motor can vary in power and torque, depending on the type and model of the e-bike.
Battery
The battery stores the energy that the motor uses. It can be mounted on the frame, the rack, or integrated into the downtube. The battery capacity and voltage determine the range and speed of the e-bike.
Controller
The controller regulates the amount of power that the motor delivers. It can be programmed to have different levels of assistance, such as eco, normal, or sport. The controller also communicates with the display and the sensor.
Sensor
The sensor detects the pedaling speed and force of the rider. It can be a cadence sensor, a torque sensor, or a combination of both. The sensor tells the controller when and how much to assist the rider.
Display
The display shows the information about the e-bike, such as the battery level, the speed, the distance, and the mode of assistance. It can be a simple LED indicator, a LCD screen, or a smart device connected via Bluetooth. The display also allows the rider to adjust the settings of the e-bike.
Conclusion
Electric bikes are a great way to enjoy cycling with less effort and more fun. They use a combination of a motor, a battery, a controller, a sensor, and a display to provide electric assistance when you pedal.
You can choose from different types of e-bikes, such as hub motors or mid-drive motors, and different levels of assistance, such as eco, normal, or sport.
Electric bikes are also eco-friendly, as they use less energy and emit less carbon than cars. Whether you want to commute, explore, or exercise, electric bikes can offer you a new and exciting way to ride.