It starts with the motor rating. And I'm not talking about the 4000kV. I'm talking about max volts and max current or power ratings of the motor. You select your battery and ESC based on those numbers. All kV tells you is how fast the motor turns per volt. And the higher the number the less power it has - yes less. 4000kV is something a quadcopter would have, not a decent truck. For power you need big wires and that usually means lower kV. So look at the max voltage and current/power rating on your motor. If it will take more than 12 volts then your 3S is ok. It not your battery is too big. And while putting 14 volts into an 11 volt motor may work for a while soon you will let the smoke out.
Last edited by rgburrill; 06-08-2020 at 08:18 AM.