Brushless experts please read

[Serum]

1 yes, basicly it is. but this number gives you the amount of mass (torque) that can be moved in a certain time (rpm)
2 yeah, dead on, Ohms law; P(power)=U (voltage) x I (current) Current and voltage will vary; the voltage will drop under a higher load.
3 Yes, output power of the motor; the entire drivetrain will eat his share of power too. like 400watts on the motor, and 300 watts at the wheels (gears, bearings , time/energy it takes to get/keep parts moving)
4 in large lines; the lower the KV of the motor (from the same series) if they are wind at the same method (delta or wye) the lower KV will have more torque and can be geared taller. the 7700 can be geared lower with about the same poweroutput at the wheels.
5 this is something weird; A lower KV is usually ran at a higher voltage; if a high KV motor is used at 7V and should deliver 700watts, the current that's needed will be 100A, if the low KV motor runs at 10V, the 700 watts take 70A. (P=UxI)
6 Yes, The higher the voltage, the less the internal resistance becomes a factor. Thats why you can use aluminum as a conductor for high voltage long distance energy transport.

[Scoob]

Originally Posted by Serum

4 in large lines; the lower the KV of the motor (from the same series) if they are wind at the same method (delta or wye) the lower KV will have more torque and can be geared taller. the 7700 can be geared lower with about the same poweroutput at the wheels.

So would you say as long as the gear ratio can be achieved for a low KV motor to match the high KV, there should be no need for the high KV motor even on a low voltage? The reason for the constant voltage issue is that I race 1/10th and voltage cannot be upped. Does a higher turn motor have higher resistance or am I off base there?

This confuses me only because I have tried to match MM5700s with my MM4600 on 2s lipo in my T4 by gearing up as I wasn't allowed more voltage. I could get the same top speed but the 4600 got hot quicker than my friends 5700s and seemed more sluggish. We were all running TP8000 2s lipos. This is why I assumed it was having trouble accepting the current the extra gearing was asking for due to resistance. I will say though that it was a one time experiment and I bought a 5700 shortly after for that large track. There may have been something else going on with my setup.

Thanks a lot for the info.:dft009:

[kufman]

To get the same performance out of a lower Kv motor you need to have higher voltage. You are correct when you say that the higher turn motor has more resistance. So.... at a given voltage you can't get as much current to flow through a higher turn motor. V/R=I

There does seem to be a non-scientific "sweet spot" for a given motor geometry. For the MM maybe that spot is the winds used in the 5700. I know in the Lehner basic series, the sweet spot seemed to be with the 4200 version of the motor.