Re: dual freewheel front sprocket drive
Hi Cabinfever - The system I designed and built is different from the Cyclone systems as well as others that drive through the derailleur/rear hub (SickBikeParts, Elation and Eclipse) in that the freewheel that frees up the motor when under pedal power is on the bottom bracket spindle. All the others have the freewheel on the motor and the motor-driven sprocket (on the BB spindle) is bolted or riveted to the pedal-driven sprocket. In those systems the motor chain is driven by the pedals, causing some excess drag. Also the smallest motor freewheel sprocket is 14T, where my motor sprocket is 9T. The Giant has been discontinued and replaced by the Sanyo Eneloop, a $2300 front hub drive. The Cyclone single chainring system has the motor down in the lower chainline, subject to water, mud and debris. It's all about compromises. Mine can't be used for regen or pedal-start (rules out most 2-cycle CGs) because of the freewheel.
I put a 350W Unite MY1016Z3 (w/built-in gear reduction) and took it out for a short test drive during a break in the weather. There didn't seem to be any problems. I used a little pedal-assist and had good hill-climbing ability in the lower gears and reached an estimated 25 mph in 8th on the flats - jd
In theory there is no difference between theory and practice. But in practice, there is - Yogi Berra