But is there any disadvantage?If you lower the gearing, you lower the speed and increase the torque. If Powacycles can climb well then this indicates that they have high torque.
I had thought the suggestion would have caused more debate. The fact is that the Powacycle bikes aren't particularly high torque,. Torque in regard to electric motors is a function of current, more current more torque. If the Powacycles produced higher torque than the common 36V Bafangs then they should draw more current, but they use similar 20A rated controllers, and similar rated batteries, they are very economical further proving that they do not draw high currents.
The 24v Bionx motors I have used all climb faster and have higher top speeds ( .c. 20 mph ) than the Powacycles and can come with similar batteries, but used in full power only mode the Powacycle have a greater range.
I would suggest that the Powacycles climb well because they climb at a low speed that requires only low power.
In terms of value they win hands down, a complete bike for less than the price of a kit, I'm a fan of Powacycles having sold a few.
Lowering the battery voltage has the same effect as using less throttle and certainly won't improve hill climbing. So there is no real advantage in doing this.
The Powacycle motors do indeed perform like 36V motors used at part throttle.
My point is that we sometimes chase absolute power for it's own sake. The hub motor with, what I have long felt to be the best combination of speed, hill climbing ability and economy is the 408 Crstalyte run at 36V. It would cruise at 20+ mph, pull my U plus 2 with my 2 boys encouragement, and still manage a respectable range ( when solo over 20 miles on a 8 AH battery), but it outputted only 360W. My similarly rapid Bafang would struggle on more than about 1 in 12 with the boys on tow. I stopped using them only because they are too big, too heavy and too ugly to be fitted to decent bike, built to handle and be as light as possible.
I have currently fitted a controller with a 15 A programmed current limit for my SWXK, the steepest hill I use daily is 1 in 7, I only use this for fun as I could take the short route home, I always use part throttle to climb it.
Can I try another provocative statement?
The only advantage of power even on hills is speed, but this comes at the detriment of range.
Try an experiment next time your on a straight moderate climb, see how far you can throttle back without you or the motor losing vast amounts of momentum. You will slow but half throttle seems to give far more than half speed.
This is akin to the advice given by Cytronix.
As soon as I can find my phone with the images on I have 3 new products, two of which I have tested.