What I thought was a fuel issue previously is looking more like one of my cylinders is going out when the outboard heats up. Yamaha 50 2-stroke 2004 From 0-3900 RPM the outboard runs just fine. From 4000-4900RPM the motor will for no reason while running drop to 4000 RPM and 10-20 seconds later jump back up to 4900RPM. When running over 4900RPM the motor does it, but less frequently, I think. WOT is 5300 RPM. The outboard has brand new fuel lines, brand new fuel filter assembly, brand new QD sockets, brand new fuel pump, and the carbs were just rebuilt. This leads me to believe something in the ECM/ECU/PowerPack/Stator is heating up at a certain temp and expanding, or one of the coils is going bad or also having trouble with the heat. How does one go about testing this at home? I could test it out on the water I guess, and bring a spark checker with me and somehow look backwards at the motor while running? lol Or I can bring my digital MM with me while out on the water and do some voltage measurements when the outboard gets hot from being at WOT- but I can't do any of this on the hose at home. Is there ANYTHING I can do at home to diagnose it while it's warmed up from idling? I am going to unscrew the bowl screws in my carbs tonight and bleed out whatever is in there and see if there is any sediment in the bowls warranting another carb clean...but I doubt it.