Electric Motor Question?

[ElectricOnly]

looking at motors and can't seem to figure something out. if you go by the formula
V*A=W what every KV I pick to get me at 30K my amp draw would be higher than the motor specs.

Gold Leopard LBP4065/4Y Max Amp 60A LiPo Cell 35V 1400KV 2000W

this is the motor I want to you on 6S but the math states I would draw 90A clearly over what is stated in the specs. MY QUESTION: Is the spec stating that at 35V the motor will produce 2000W but in reality it can handle a much high Amp draw.

Thanks
Ryan

[Fluid]

This can be confusing Ryan, and there is no simple way to "do the math" for everything. A lot has to be from experience, yours and that of others. The motor specs are not carved in stone, and in some cases we normally exceed the listed amp draw - it can depend on the motor and how it is used. Those specs are guidelines, and some makers are more conservative in their specs than others are.

In your case, the 4065/4Y on 6S will likely be spinning around 28,000 rpm at 100 -120 amps draw. This draw is normally not a problem as long as the motor is water cooled and is not run for more than about 2-3 minutes at a time. That's 2400 watts used from the cells with around 2000 watts at the prop due to motor and ESC inefficiency. But it is easy to draw far more than 120 amps just by using too large a prop or running the boat too wet. The availability of dataloggers and ESCs with this feature (Castle ICE) makes it a lot easier to tell what you are actually doing. Math alone doesn't get you there.


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[keithbradley]

Are the gold leopards the 2 pole versions? The 4 pole 4074's that steve sells here at OSE are slightly longer and rated at 120A. If you are looking for a little more power you could go that route. They are available in quite a few different winds.