Limiting top speed without losing Torque

Hello, I am working my build and I am almost finished. I find it difficult to really understand the best way to limit top speed without the loss of torque. I am required by law to limit the speed to 20 km/h, which for many is slow but works for me. Some people have suggested setting an ERPM limit in the VESC tool and someone told me that that is dangerous as breaking would not work when the motor exceeds the ERPM limit i.e. down a hill. Others have suggested just lowering the maximum duty cycle. Which should I do and why? :slight_smile:

1 Like

Lowering the Maximum ERPM only turns off the ESC above that speed — including turning off the brakes. That’s really for other things and probably more useful on an aircraft propeller or something, than on an esk8.

To set a hard limit on the board’s speed for legal or safety reasons, you can change the “Maximum Duty Cycle” to some amount less than the default 95%

AND THEN make “Duty Cycle Current Limit Start” about 5% less than that.


Full speed:

  • Maximum Duty Cycle 95%
  • Duty Cycle Current Limit Start 85%

Half speed:

  • Maximum Duty Cycle 50%
  • Duty Cycle Current Limit Start 45%

Low speed:

  • Maximum Duty Cycle 25%
  • Duty Cycle Current Limit Start 22%