just purchased a 18' lund with 2006 honda 90. The boat is going around 24 MPH with a 18 pitch prop and 3200 rpm at wot. I cleaned the carbs changed the plugs and still can only get 3200 rpm out of the motor. tried different prop pitches but still low rpms. at wot the carbs are all fully opened with the linkage. can anyone help me figure out this problem? Boat starts great and sounds really good but just feels like we are running at half throttle.