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johnrobholmes · 12.02.2007, 09:00 PM

If you raised the kv back up to negate the wye termination, you would indeed lose the torque bonus.

Kt = 1352.4 / Kv By this formula the torque constant and kv are directly related for any and all electric motors. Like I said before, if the overall construction of the motor is not changed the power of the motor wont change. Different terminations or winds only change the voltage and amperage that the motor will produce said power. The torque curve won't change, the wattage wont change, the motor is still the same motor.

I have fought this issue with guys at RCC for a while now. People thing a 65t motor will produce more torque than a 55t motor. Geared for the same wheelspeed they will produce the same torque and power if the rpm of the motor is also the same. This means a different voltage for the two setups. On the flipside, if gearing and voltage is held constant the 55t will have more power since it spins faster and has a higher amp draw. A third example is when wheelspeed is kept the same through different gearing with fixed voltage. A 35t motor on 3s lipo geared way down will have a ton more power than a 65t on 3s lipo geared for the same wheelspeed. Lower turns, but more torque through amperage and gearing. In your case you cannot change the gearing except with tire changes, so we have one less variable to deal with.

Between two identical motors with different winding:
Same gearing, same wheelspeed (indicates same rpm at motor), different voltages to hit said rpm. If the vehicle hits 60mph it will take the same wattage no matter what the motor if vehicle weight is constant. Same power, just at different voltages.

The aspect we are really going for is a better low speed commutation of the motor, correct?. Although the motor will have the same performance capability no matter what wind or termination, the ESC might do better with certain ones.

The 4045 is a huge motor. Getting a kv so high will be very tricky.

	(#219)
johnrobholmes RC-Monster Aluminum Offline Posts: 905 Join Date: Aug 2007	12.02.2007, 09:00 PM If you raised the kv back up to negate the wye termination, you would indeed lose the torque bonus. Kt = 1352.4 / Kv By this formula the torque constant and kv are directly related for any and all electric motors. Like I said before, if the overall construction of the motor is not changed the power of the motor wont change. Different terminations or winds only change the voltage and amperage that the motor will produce said power. The torque curve won't change, the wattage wont change, the motor is still the same motor. I have fought this issue with guys at RCC for a while now. People thing a 65t motor will produce more torque than a 55t motor. Geared for the same wheelspeed they will produce the same torque and power if the rpm of the motor is also the same. This means a different voltage for the two setups. On the flipside, if gearing and voltage is held constant the 55t will have more power since it spins faster and has a higher amp draw. A third example is when wheelspeed is kept the same through different gearing with fixed voltage. A 35t motor on 3s lipo geared way down will have a ton more power than a 65t on 3s lipo geared for the same wheelspeed. Lower turns, but more torque through amperage and gearing. In your case you cannot change the gearing except with tire changes, so we have one less variable to deal with. Between two identical motors with different winding: Same gearing, same wheelspeed (indicates same rpm at motor), different voltages to hit said rpm. If the vehicle hits 60mph it will take the same wattage no matter what the motor if vehicle weight is constant. Same power, just at different voltages. The aspect we are really going for is a better low speed commutation of the motor, correct?. Although the motor will have the same performance capability no matter what wind or termination, the ESC might do better with certain ones. The 4045 is a huge motor. Getting a kv so high will be very tricky.