Thanks! I've never measured the efeificncy of the system. But I can see the flow of the electrical power which coming in and out. I always turn my 80-90rpm on the crank, that's optimized for the muscles.Wtih the generator I only can produce constant 3A@40V=120WATT, for a very short time 9A=360WATT. The most lost energy to ride uphill I can get back with the recouperation downhill.The tare weight of the bike is 98Kg, roadworthy about 110Kg and additional with me(90Kg) = 200Kg!