miuan wrote:d8veh wrote:The most important thing is to match the motor to your normal speed that you expect to be going. It can make a significant difference to your range if you have a mismatch. When a 393rpm motor is laboring up a steep hill at 200 rpm, efficiency could be as low as 60% compared with the maximum of 78%, while as a 201rpm motor would be achieving the 78%, but you only get half the top speed.
You do get half speed with slow wind, but DO NOT get 60% efficiency with fast one while the slow is doing 78. The difference can be couple per cent, not more. I go as far as assuming you get even more losses in the controller/wiring than the difference in motor efficiency, if you decide to use same voltages on both systems. Simply because you need to half the voltage and double the current with the fast motor, while just passing all the voltage to the motor with the slow one.
Have a look at the Ebikes.ca simulator. Choose the Ezee motor as the nearest equivalent. Top speed at 36v is 30kph with efficiency of 78%. On a 10% incline, it slows to 15kph with an efficiency of 64%. That means that your wasting 18% more.