How I Made My Road Bike Electric

Adele Valeria
5 min readOct 29, 2024

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The finished e-bike :)

I recently converted my Fuji hybrid city bike into an e-bike using the Bafang BBS02 kit, which I purchased from AliExpress (shipped from the United States) for about $680. The kit includes a 48V 19.2Ah downtube battery, a 750W motor, an EKD01 display, and a 44T chainring.

My main motivation for doing the conversion myself, instead of buying a pre-made e-bike, was to build a higher-performance bike at a lower cost. Besides, I was already comfortable with my manual bike, so I thought, why not just upgrade it?

Before actually purchasing the kit, I assessed compatibility by printing cut-out templates for the bottom bracket and battery to ensure they would fit my Fuji bike frame. Everything looked good.

After several days, the kit finally arrived! I was able to get started right away, thanks to the wide range of bike tools generously lent to me by my housemate: crank and bottom bracket removal tools, a pedal wrench, a bike stand, and various Allen wrenches. The only extra items I needed to buy were a longer adjustable wrench for extra leverage (our existing tool could not remove the crank arms), dielectric grease, and cable wrap.

Inserting the BBS02 motor into the bottom bracket shell.

To install the Bafang BBS02 kit, I first removed the crank arms and bottom bracket. I then proceeded with the following steps:

  • Inserted the motor into the empty bottom bracket shell and secured it with the provided bolts and lockrings. Make sure to secure the lockrings super tight! I made the mistake of not tightening them enough. On my first ride, I noticed the motor was moving upward and hitting the frame when I used the throttle or pedal assist. The pedals also felt a bit wobbly. It felt strange, but I was inexperienced with e-bikes and thought it was normal. I even bought a pad to cushion the motor so it would not hit the frame too hard 😂. Later, I read online that the motor is not supposed to move at all while riding! I had to remove the pedals and crank arms again to properly re-tighten the lockrings and bolts. After that, everything felt solid, and there were no more issues!
  • Attached the 44T chainring to the motor and reinstalled the crank arms and pedals.
  • Removed the left shifter permanently to make space on the handlebar (and because I thought I would not need it anymore).
  • Replaced the existing brake levers on both sides. When purchasing the kit, you can choose between electric bike levers or sensors. I opted for the levers, so I replaced the originals with the Bafang-provided ones. To install the new right brake lever, I had to temporarily remove the right gear shifter since it is positioned to the right of the brake lever.
  • Installed the display and throttle on the left side of the handlebars.
Left brake lever, EKD01 display, and throttle. The display shows your battery level, mileage, and speed. To increase the speed, press the ‘+’ button, and to decrease it, press the ‘-’ button. The default maximum speed is set very high, but you can lower it in the settings. The display also requires a password to operate.
  • Mounted the battery bracket to the downtube by securing the bolts into the water bottle mount holes. My setup is a bit tight — there is not much space in front of or above the battery, but I can still remove it without too much trouble. Bafang does offer batteries designed for mounting on the rear rack, but I chose to mount mine on the downtube for better balance. Besides, I like to keep my rear rack free for a basket to carry stuff!

Important: ensure the battery is not attached to the bracket when working with the cable connections. I accidentally burned the metal part of a bonus XT60 male connector cable when it hit the bike frame while the battery was attached!

  • Mounted the front light to the front fork using zip ties. However, I usually keep the Bafang-provided light unplugged because it stays on whenever the battery is connected, even when the display is off and the bike is idle. To save energy, I rely on my own front light instead.
  • Mounted the speed sensor to the rear wheel and frame using zip ties.
  • Applied dielectric grease to the male part of all connections to protect them from corrosion, then connected all components, including the display, throttle, motor, and brake sensors.

Tip: The cable connections can be very hard to remove. To make it easier, try blowing warm air over them with a hair dryer — it worked for me!

  • Organized the cables using a spiral cable wrap to ensure they were tidy and would not interfere with any moving parts.

Bonus upgrades: I replaced the old saddle with a more comfortable one to improve my riding experience. I also changed the front tire to one more recommended for e-bikes, though I kept the rear tire for now since it is still in good condition. Additionally, I installed two collapsible rear side racks to expand my bike’s carrying capacity, which has made it much easier to use the bike for grocery shopping!

Overall, doing the e-bike conversion has been a great learning experience. I love working with my hands, including assembling and disassembling things (a budding hobby that began when I restored a vintage knitting machine). However, I have not had much experience working with bikes, so I did get annoyed at times, particularly when adjusting the brakes, right gear shifter, and rear derailleur. Thankfully, I managed to complete the conversion with the help of many YouTube videos and Reddit threads (here are more tips and tricks). I even feel quite satisfied and proud of what I accomplished. That said, I am still not sure if I did everything perfectly — but hey, it seems to be working fine! Do you install your kit differently than I did? Feel free to share your conversion experience!

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