The stator generates 3-phase AC output as long as the engine is rotating.
The rectifier/regulator rectifies the 3-phase AC to DC current and regulates the voltage from 13.5 to 14.5 VDC on average.
It shouldn't be below 13 VDC (insufficient battery charge current) or above 15 VDC (excessive charge current).
If you experience a loss of charging if you hit a bump, I'd first suspect a loose electrical connection.
The stator lead plugs directly into the rectifier/regulator mounted on the left part of the sub-frame. Make sure the connector is securely made and if disconnected, check for corroded pins. This happens over time.
Check your battery leads and made sure they are snug along with the main electrical ground lead on the right frame area just above the sub-frame bolt.