The current generated by an electric motor while spinning, under power or not!! is reverse to the external power supplied. It is the motors efficiency as a generator which has marked effect on it's max revs. EMF generated will create its own magnetic field countering that of the supply until it eventually causes the motor to peak. ie it won't rev anymore. This is Lenz's Law
Lenz's Law states
"An induced electromotive force generates a current that induces a counter magnetic field that opposes the magnetic field generating the current."
Also..
When the controller brake is connected, on passive over run the emf generated is trying to cause the motor to run in reverse but it never will for as the motor tries to stall, so the reverse emf reduces.
Clear as day!
Also, as an alternative to having a pot as a variable brake control, I have eventually opted for a three position switch wired into the brake line, this introduces either a 10 or 20 ohm resistor into the brake line. It's more positive than a pot and is fairly knock and accidently adjusted proof. It works fine on thing like Ninco Go karts which end up braking side on! to taming some of the SCX 4WD Rally cars.
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Lenz's Law states
"An induced electromotive force generates a current that induces a counter magnetic field that opposes the magnetic field generating the current."
Also..
When the controller brake is connected, on passive over run the emf generated is trying to cause the motor to run in reverse but it never will for as the motor tries to stall, so the reverse emf reduces.
Clear as day!
Also, as an alternative to having a pot as a variable brake control, I have eventually opted for a three position switch wired into the brake line, this introduces either a 10 or 20 ohm resistor into the brake line. It's more positive than a pot and is fairly knock and accidently adjusted proof. It works fine on thing like Ninco Go karts which end up braking side on! to taming some of the SCX 4WD Rally cars.
