The most common reason for your ESC / Motor damage is found by "overloading"
It is hard to accurately check the "load of a vehicle system, but there is a simple method.
Measuring the temperature of ESC and motor.
If the ESC temperature (measured from outside at the hottest position) is over 85 degree (for low-cost thermal instrument with low accuracy) or 90 degrees (for high-cost thermal instrument with high accuracy), or the motor temperature is over 90 degree or 100 degree, your system configuration must be changed immediately that a load of vehicle is too heavy for your ESC or motor.
In such a case,
change your gearing ratio by using a smaller pinion or bigger spur gear by one. Check the temp again after running a few laps until you find the perfect ratio. "Stock gearing" does not mean your system with upgraded electronics works perfectively.
Airplane / Heli
change PROPS SIZE, by sizing down to smaller propellers. timing set to 0, Reduce voltage, Check the temp again after running a few minutes until you find the perfect size.
change PROPS SIZE, reset betaflight, no timing, Reduce voltage, Check the temp again after running a few minutes until you find the perfect size.
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