3D-printed Electric OFO Bike Mod

Hi, rental bikes such as OFO are a great transport in the city but they often do not support different gear speeds. Here is a DIY 3d-printed mod to convert any OFO bicycle to electric. It only takes 2 to 3mins to mount the DIY controller and the DIY friction-drive unit to the bicycle and you have an electric-assist system to help you go up-slope. Below are the parts used for this project. Simply follow the youtube video for the build steps.
https://www.youtube.com/watch?v=JiyEnpMJHTM

Frictio