Bionx motor – modification

Start by watching the episode about conversion on our YT channel 🙂:


  1. I recommend this motor to DIY enthusiasts who build a bike up to 1500W.
  2. This motor is cheap to get on the aftermarket because people import bikes with these systems as damaged, convert them to regular bikes and sell wheels as unchecked or damaged. It is very possible that they are actually damaged, but it does not bother us at all!
  3. Most often in these systems controllers that are inside the engine break down, and we throw this controller away!
  4. The engine is light (about 4.5kg), gearless (which makes it maintenance-free),
  5. has hall sensors (better start from zero than sensorless).
  6. Looks good and pushes well up to 1500W 🙂.


We convert this motor to an external controller and add thermal protection against overheating, and replace the bearings with new ones.

Such a converted motor can be connected to any BLDC motor controller / controller that supports hall sensors (most of it has). The power in electric bikes is maintained mainly by the controller, so we are not limited only to statutory 250W.

This engine will pull up to 1500W without damage. It’s not recommended to push this motor beyond 1500W becouse it has relatively small magnets and coils. It means that it will not produce much more more torque and will heat.


Fortunately this list is not long:

Heat Gun / burner
LIYCY cable 8×0.25mm2 (1.5mb)
1.5mm2 wire with silicone insulation (3×1.5mb)
polyester cable braid
cable ties
shrink tubes
bearings 6003 with C3 clearance 2 pcs
thermal protection 145 degrees C
LM35 temperature sensor
heat conducting glue above 200 ° C
car spray black semi-matte (for rims, bumpers etc.)
sockets / bushes for knocking out and driving in of bearings
water spray, cloth

Good luck 🙂!


Stay tuned 🙂:

FB group e-BIKEL-owcy technically about electric vehicles

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In the Facebook group we exchange experiences and comments on electric vehicles

Spot welder machine

Do it yourself

Spot welder / do it yourself
Spot welder / do it yourself
  1. Single and double pulse cell spot welder, made of a transformer from an old microwave oven.

  2. Controlled by Arduino nano microcontroller.

  3. The whole built on an old drill stand.

  4. Copper wire electrodes attached to swinging aluminum arms. Each arm bends independently, thanks to which level out unevenness and the electrodes are pressed against the welded tape with equal force.

  5. With swinging arms, a limit switch is installed, which automatically activates the welding pulse when the electrodes are pressed against the cell.

    The whole is operated comfortably with one hand, so that with the other hand we can hold the cells or tape 😜.


PCB design, diagram in eagle and code in Arduino IDE to download

When designing the welding machine, I used posts from the electrode forum


Advice for builders:

Place the controll electronics at least 30cm from the transformer.

At the beginning I fitted everything, including the controller and transformer, into the housing from the ATX computer power supply. Unfortunately, this was not a good idea, because the magnetic field from the transformer generated interference and badly affected the micro-controller. The effect was that sometimes during welding the welding pulse did not disappear !!! Copper wire electrodes were evaporating at that moment, and there was a big hole in the tape ….

After moving the controller to the top of the welding machine (to the top of the drill stand – this can be seen in the first photo and in the film about welding the battery) everything is OK.


When etching the PCB from my project to refresh the PCB in Eagle with the “Ratsnest” function, so that GND mass polygons appear!


We encourage you to be up to date 🙂. You will not miss information about our projects.

FB group e-BIKEL-owcy technically about electric vehicles

Group e-BIKEL-owcy

In the Facebook group we exchange experiences and comments on electric vehicles crew