BMX to eBike Conversion [WIP]

I am working on a conversion of a BMX bike into an electronic bike. So far it is not over yet, as I try different solutions.

At first I wanted to make it a tricycle, but I encountered some difficulties. Then I wanted to add a motor of an lawn mower, but I could not find an easy way to do it. So I decided to add an electric motor.

You can see my early tests in the following video (in Greek)
https://www.youtube.com/watch?v=Srd5_jpmnnc