Testing electric motors

[Leet TC3]

I admit I get confused over some terminology, so I will try and keep this
simple: When testing an electric motor, if you have a given (constant)
supply of voltage, is it preferable to have more or less amperage?

e.g. Testing a brand new (after break in) stock motor (Reedy MVP, 24 degree)
I measured about 4.2 amps at 5 volts after running the motor (no load) for 2
minutes.

Using the same parameters with a 14t double modified motor, I measured about
2.2 amps after 2 minutes.

From this I can deduce the better motor would draw less amperage at a given
voltage. Is this correct?

[Grizzbob]

I'm afraid it's not that simple. Amp draw is only one factor in how a motor is performing, & not a very important one at that. Barring the use of a dyno(I assume you're using something like a CE Turbo35 that can supply a given amount of voltage to the motor), you could try listening to the pitch of the motor when you apply the voltage(the higher the pitch, the faster it's turning), & also how quickly it reaches that tone(that can provide some indication of torque). Those two things are much more important to how a motor is doing than how much current it draws(though if it can do the rest & draw fewer amps, all the better).... :)

[Leet TC3]

Yes, understood. I was just curious about the relationship between the amperage draw at a given voltage.

Hard to determine the pitch, but I have found heat to be a good indication too. A motor that is struggling will be quite warm after a couple of minutes at 5v.

BTW, I am using a Victor Super2.