It sure looks like my Bafang BPM so I wrote him disputing his claims and he wrote back;
"Have you seen the inside of our motors ? How do you know that? We do not use fixed reduction gearing we use continuously variable gearing that expands to different sizes as needed by the motor in order to keep the motor always at the same RPM regardless of what speed the bike is actually going. This increases the efficiency of the motor by about 35% over a simple fixed ratio reduction system. I designed the motor and I have taught motor technology at the graduate level for over 10 years. You would have to look inside the motor to understand this system. Thanks, Dr. Ross"
Has 8FUN (Bafang) developed a new motor with variable gearing???