DIY Electric Bikes

Amy Chan

When you’ve finally had enough of sitting in miles of traffic, watching car exhaust float off into the atmosphere, and you’re ready to do your part for the environment, one of the best things you do to reduce your carbon footprint is to stop driving to work. Biking to work is a great way to get there quickly while still impacting the environment. But if you encounter a big hill somewhere on your commute it might seem impossible. Putting an electric motor on a normal bicycle can help you make it up those big hills and the great news is that you can do it yourself.

The Basics

Whether you’re an amateur electrician or have never built anything before, a DIY electric bike is a project that anyone can complete. It’s a low-cost project that creates big results that are both fun and economical. Your parts will include:

  • Electric Mid Drive, 750 Watt Bafang BBS02 Kit with Led display and 25Amp controller and thumb throttle
  • 12 volt 20AH batteries
  • Smart LED balance boards
  • Series connector bars
  • LifeP04 battery charger
  • Battery box
  • Titan straps
  • Key starter switch
  • Inline 30 amp fuse and starter

Picking Your Motor

While geared hub or direct drive motors have been the most popular choice for electric bikes in the past, there’s a new choice these days. The mid-drive motor attaches to your back, wheel system and allows you to continue using the bike’s original rear derailleur when you need to change gears. You can find the right motor for your electric bike at The DIY Outlet.

This Old Thing?

If you’re worried about how you’ll afford some fancy bike for this DIY project, don’t even think about it. One of the biggest advantages of this project is that almost any bike you have can work. The one main stipulation for a bike is that it needs to have a 68mm bottom bracket shell width. You may also want to consider a few other things, though they aren’t mandatory. Having smaller wheels on your bike will usually mean they are stronger. Having more spokes in the wheels can make them stronger. Wider tires can create a smoother ride. If you’re worried about stopping on a hill, you might want to make sure you have front disc brakes on your bike. Also, having a bike that can support a decent amount of weight in the back will make it easier to hold your motor, batteries, and other parts.

Once you have your bike picked out, start by removing its’ chain, bottom bracket, and crank set. Some chains require a special took for removal. Then take a hex tool to the crank arms and a puller tool to take the crank assembly off the bike. Finally, take off the bike’s bottom bracket using the special screwdriver tool that matches your bike. At this point, you may want to clean your bike before you begin attaching new parts.

If you don’t happen to have all the specialty tools that are needed for disassembly, don’t feel shy about taking your project to a bike shop. Someone there will probably have the right tools and can take it apart in less than five minutes; they may not even charge you because taking it apart is so simple.

When the bike is disassembled, you can then attach the mid-drive kit. It should slide through the bottom brackets and then be screwed into place. Screwing it in can be difficult so make sure to check for any loose screws and know that it may have to be tightened occasionally.

The Battery Box

If you already have a rear rack, installing a battery box should be pretty simple. A cargo style rack is ideal and you can easily construct your own if you need to. Just measure your battery box and then build an outside container to hold it and keep it from sliding around. If it slides while you’re riding the bike, this can cause balance issues. Once you have something constructed to hold it, just simply use two Titan strips with screws to hold it in place.

Creating Your Battery Pack

Creating the battery pack for your bicycle can be one of biggest challenges of building your electric bike. There are several suppliers from which you can purchase pre-made, triangle-shaped, battery packs online and these are perhaps the easiest option when it comes to a battery pack for your electric bike. Most of them will cost you around $100. When you receive your batteries, make sure that you thoroughly test them. You may need to add your own connector bars between the batteries if you decide to construct your own pack. Be sure to cover the pack by wrapping it with duct tape and you can use packing material to wedge between the batteries and box. Next, you’ll need to add a key switch so that you can start your electric bike easily.

Final Touches

For safety and easy storage, you’ll want to add a few additional elements to your electric bike. A kickstand that is able to hold the bike’s weight is incredibly important. You’ll also want from and rear lights, including brake lights, and these can be run from the bike’s battery. A horn is also a great addition, for safety. Remember that your bike will never keep up with cars and because it’s likely you’ll have to ride in some traffic, you’ll want to have these safety elements installed before you take your new bike on the road.