I have not tested this, but the parameter inertiainit can be set = 0 to turn it off on startup. Also, it can be turned on and off with the transmitter:

The inertia (momentum) can be enabled automatically at startup by setting the appropriate value,
also it can be turned on or off by transmitter.
For Base version only one curve is available
For Full Option version there’s up to 6 different pre-loaded curves, you can set the desired one by
setting the related value
InertiaInit=0
Set inertia status at tank power on 0=Inertia OFF, 1=Inertia ON (at start up)
InertiaType=1
Set the desired inertia curve

I like the inertia. When you just let off the throttle, the tank slowly comes to a stop. If you want an abrupt stop, reverse stick. This engages the "brakes" and the tank stops immediately and the brake lights come on.

Steve