[VintageMA]

Thanks Patrick - great informative explanation!!

That along with the graphs also helps a lot explain the downside of being either very over-geared or under-geared. You're not running in the peak efficiency of the motor and more power is being turned into heat than mechanical energy.

Also helps to explain how using too big a motor for the application can be inefficient, and also how using too small a motor can also be inefficient but in the other direction. If you ask a small motor to put out too much power you then surpass it's eff% range and you start to get more heat and less mechanical output - where with the larger motor you get the same inefficient result but just because there's not enough load on the motor.

Also explains why you shouldn't be running your motors at no-load - eff% is very low there and almost all energy going into the motor gets turned into heat - why they heat up in your hand very fast when testing.