[Water Warrior 2]

Hmm, 2 things come to mind. Your GZ doesn't like that speed very much. Secondly the float in the carb might be sticking and flooding the cylinder so badly that you are washing down the cylinder walls, loosing the seal of the rings and diluting the oil. Old school trick is to tap the float bowl with the handle of a screw driver to loosen up the float. You want to correct the situation soonest or have the engine grenade due to diluted oil and no lubrication.