billdelong

the best current limiters shorten the duty cycle (PWM). that is the main thing you ESC does. its is a current limiter. if you want to limit it more then set the end point shorter.

you have 1 of 2 problems and I’d start by isolating the two systems to figure it out.

1-you have an electrical resistance problem
2-you have a mechanical binding problem.

if its electrical, measure the voltage before and after the hotspot while under load. this will tell you dynamic resistance (and its a very cheap method to measure very low resistances that a high dollar LCR would measure). a big drop on the output side (voltage) without much of a drop on the input is resistance (you can measure current to have all the values in ohms law but even using a guess is fine). if the drop is close to equal then look at mechanical.

if its mechanical start isolating components. left, right, front, rear. A dif checker does pretty good at checking specific points for friction. you can also use weight an a lever arm at a know distance. once you get it in good running order measure the current at the motor at say 5000 rpm. keep that number handy because you can use it to check friction over time.