new air filter also

It is possibly the Ignition Interlock, a safety device usually under the cover by the shifter lever. You don't say what engine, always helpful. The engine probably has a terminal where a bunch of wires junction, likely on the side of the throttle box, where the throttle cable attaches to the engine. Disconnecting all wires from this will help to tell where the problem is. Keep in mind that you now have no way to turn the engine off without shutting off gas, pulling plug wire or something that way.

"Old 90s riding snapper cut off when it twisted"

Explaining what you mean here might help. IF you went over some irregular ground causing the frame tube to twist, may well be a short in the "Kill Wire" coming from the switch IF the switch is on the steering post. It may be shorting against the clutch cable which runs thru there also.

Walt Conner