How to Build an Inexpensive Electric Bicycle
An electric bike is a lot easier to build than you might think! All you need is a bike in good working order, a conversion kit, and a battery. Using a conversion kit makes the process super simple and fast. Shop around online to find the best deal on the kit and repurpose a bike you already to make this an inexpensive project.
Gathering Your Materials
1. Select a bike with small wheels, front disc brakes, and wide handlebars. If you don't own a bike already, search online or in your local area to find a second-hand bike at a good price. Luckily, you can use just about any bike you have on hand, though certain features will yield the best results:
Generally, the smaller the wheels are and the more spokes they have, the better the bike will be able to support the added components.
Wider handles bars are best as they give you plenty of room for all your accessories and lights.
Front disc brakes will make it easier for you to stop on steep hills.
2. Pick up an electric bicycle conversion kit. If you’ve never built an electric bicycle before, a conversion kit will make the process much simpler. These bolt-on kits contain a throttle, speed controller, and a wheel with a hub motor. Some also come with gauges, displays, and brake levers, though these are not strictly necessary.
Ensure the kit comes with a wheel that is the same size as the existing wheels on your bike!
For ease of installation, it’s best to purchase the battery and the conversion kit from the same manufacturer.
3. Choose a 36- or 48-volt battery with a capacity of 10Ah or 20Ah. Be sure to choose a battery designed for use on an electric bicycle, as it will come with a charger and be much easier to install. The higher the voltage of your bike's battery, the more powerful your bike will be. When building an electric bike, choose a 36- or 48-volt battery to allow for speed and comfort.
The capacity of the battery defines how long it'll last. If you’ll be taking short trips, a 10Ah will suit you well, while a 20Ah battery will provide you with extra capacity for slightly longer journeys.
Replacing and Adding Parts
1. Put the tire from your old wheel on the new wheel with the hub motor. Remove the old wheel from your bike by loosening the nuts on the axle with a wrench and pulling the wheel free. Then, let the air out of the tire and use a tire lever to separate the tire from the wheel. Pull off both the tire and the inner tube. Reverse the process to install the tire and inner tube on the wheel that came with the conversion kit.
They type of kit you purchased will dictate whether to use the wheel on the front or back of the bike.
2. Attach the speed controller and the throttle. Follow the directions in the conversion kit for installing these 2 parts using the included hardware. Use the provided bolts to secure the speed controller to the frame of the bike above the chain. Then, attach the throttle to the handlebars so it’s easy to reach.
If you have any other accessories, attach them as well. Secure the speed sensor to the back wheel and connect any displays and gauges to the handlebars with the included hardware.
3. Connect the battery to the speed controller and the throttle. Follow the instructions included with the kit to connect each part. Typically, you’ll only need to plug the connector on the speed controller into the connector on the battery, then repeat the process for the throttle. Be sure not to touch the battery wires together, as this could create a dangerous spark!
4. Mount the battery onto the bike. Most e-bike batteries are designed to fit on the frame in place of a water bottle holder. This is the ideal placement since it keeps the center of gravity low. Use the included hardware to attach the battery to the frame as indicated by the instructions that came with the battery.
Alternatively, you could place the battery in a box or basket on the front or back of the bike, particularly if it is too large to fit well on the frame (such as if it’s more than 60 volts).
5. Secure any loose cables. Use zip-ties to attach any loose parts to the frame. Keep safety in mind as you don’t want any cables to get caught while you’re riding.
6. Ride your electric bike. That’s it! You can now cruise around on your e-bike. Just press down gently on the throttle when you’re ready to ride. Go for a test drive in a less populated area so you can get used to it before you take it out on the road.
7. Charge the bike when necessary. The e-bike battery comes with a charger, making the process super simple. Follow the instructions for connecting the battery to the charger and plug it into a compatible outlet whenever you need to.