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Ohms law Resistance = Voltage / amps, in this case the total resistance of wires, motor, speed control, etc
1.22 volts @ 106ma = 11.51 ohms (1.22/.106=11.51)
1.22 volts @ 172ms = 7.09 ohms (1.22/.172=7.09)
Difference is 4.4 ohms that seems like a BIG difference to me....were you using the same motor for both tests? Was the gearing the same? Was the load the same (ie spinning tires in the air)?
Another (better) way to run this test:
1) make sure both cars are identical drive train wise (motor, gears, fresh charge)
2) measure the battery voltage with tires spinning
3) measure motor voltage with tires spinning
4) measure current with tires spinning
5) the speed controller resistance is calculated with the formula:
(Battery voltage - Motor voltage)/motor current = ESC Resistance
for example: Battery Voltage = 1.22, Motor Voltage = 1.12, Motor amps 170ma (or .170 amps) gets you .588 ohms
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