For my electric bicycle, I wanted to have a freewheel sprocket on the MY1018Z motor. This would allow me to pedal the bike with the motor turned off without any drag caused by the motor's shaft spinning. However the only sprocket that came with the motor is a 9 tooth fixed sprocket. This video shows how I made a shaft adapter for the freewheel sprocket out of the original 9 tooth gear that came with the motor.

Check out this video of my electric bicycle using this finished freewheel sprocket:    • Homemade BB Drive Electric Bicycle