I have a 1991 Yamaha Waverunner 3. It is a wra650p engine. I have noticed a problem that seems like an engine miss after approximately 15 minutes of running time. I have rebuilt the carb, new fuel filter, trimmed back the wires, and done a compression test showing 150 lbs on both cylinders. I have changed the spark plugs when it starts missing, and it didnt help. I disconnected the temp sensor in the electrical box, which didn't help either. I don't really know where to go from here, and was hoping someone could lead me in the right direction. Thank you in advance!