Hi Andrew, as you are using minimotors, it should be OK to do it that way, but make sure you don't disconnect the controller that's providing the +5V throttle supply.
If you were using dual Pies, I would suggest putting a switch on the throttle signal wire going to one of the controllers
(not the main throttle lead as shown in the immobiliser circuit below) to disable the throttle, but still allow regenerative braking from both motors.
A 12K resistor should be fitted between the +5V and the throttle signal to prevent the disabled controller from activating throttle failure mode.
An alternative method would be to fit a
DPDT switch as shown below to enable either or both motors to be selected as required.
I hope you're not too confused now.
Alan
