I have no manuel, and will check the sensor because it was rebuilt and when turn the handle bar the head light goes out some times, checked the coil packs on the plugs with ohm meter and reads .01?a tip sensor is a sensor that cuts spark to the engine in case of a wreck. If tilted past some degree theta, it cuts it off.
But, if you were riding and it just stalled, it is unlikely, i dont see this thing just failing out of the blue.
Perhaps a connector melted to the coil packs. Do you have a manual?