You are actually a little backward on the voltage and amps. Amps would be the amount of water and volts is the pressure. Higher voltage (higher pressure) forces more current thru the motor (amps) and can over heat everything if THEY are not rated for it. You are correct about the rest.

Artman, I am not sure what you are doing. If everything is overheating you are trying to get more power than your equipment will handle. You have to upgrade the equipment or lower what you are pulling. You do this by either lower voltage and/or smaller prop. To stay with what power you are getting, you need to look at what you just did. The esc was getting hot. You got a bigger esc. The batteries got hot so you got bigger batteries. Now the motor is still too hot? You have to get a bigger motor! Then you will be in good shape.

The only other thing you can do is cut back on the demand on the motor as I mentioned above.

The ESC does NOT automatically set the correct voltage to the motor.

Keep in mind that all this stuff WILL get hot when using it and that is normal, unless you are running blistering hot. If you try to run everything cool you will have more weight than you need or even can carry. Li-Po batteries are the quickest to be damaged from extreme heat. They should never get over, about, 150 degrees F. They will feel hot at that temp, but, will be ok.

Good luck.