1. The fuel pump plunger adjusts the oil supply too much, or adjusts the ring gear locking screw to loosen and adjust the ring gear displacement, resulting in excessive fuel supply to the fuel injection pump.
2. The adjustment screw for limiting the maximum oil amount of the rack in the governor is too large or the throttle handle limit screw is adjusted too large.
3. Excessive oil in the governor will increase the oil supply and lead to "speeding".