I have a 2004 Yamaha 50HP 4 stroke (2004 F50 TLRC) and when I am at low RPM and high RPM it is fine, but when I am around mid throttle, ~24-30k RPM it seems to choke a bit and has a very strong vibration. As soon as I'm up on a plane it goes away. With only me in the boat it gets up on a plane quicker and that vibration RPM range is smaller, more like 25-28k RPM, but still there. I'm thinking this could be the carbs getting clogged up or something? It feels like a fuel shortage in the engine. Also worth noting though I'm unsure if it is related is that the outboard never gets above 45k RPM. I think it should easily be clearing 50k.
Any ideas on what this could be? Or ideas for how I can confirm it is the carbs?
Any ideas on what this could be? Or ideas for how I can confirm it is the carbs?