It would seem like M/C's would have a lanyard type switch on an HP electric pump.
Inertia switchs were normally designed for rear end collisions and not much else. So if your car is flying through air and does not land on its tail it may not work. Side collisions are also questionable at best for its actuation. Your best bet will be a "dumb luck" when your push truck drive bumps you hard and actuates on your back up record run or after you waited 3 hours to run and only get 100 yards.
Personally I don't like the rule for low pressure electric pump systems. The manufactures had to, or were required to, come up with something when standard vehicles started having 70 psi systems.