2005 225 not reaching full rpm

Thanks to everyone for your past help. I have a 2005 225 Honda. When I initially start up after it has sat for say a week it puts out a small cloud of white smoke. And then no more smoke for the few days I am on the water with it and then when I store it for a Week and come back and start it I get the white smoke and then no more smoke. Until recently it never smoked even after sitting all winter. Now I am experiencing a slight loss of power at full throttle. It usually runs at full throttle, 5800 rpms but now struggles to get to 5200 rpms. Possibly 02 sensor, plugs?? Fuel line pressure 40. Thanks in advance for any suggestions.

Firstly, if your motor is stored in the fully down position, it is normal for a little oil to sleep past the rings and settle on top of the piston until the next start up, most four strokes do this. As far As loss of power, you need to start with the basics, inspect your spark plugs, carry out a compression test. Fuel pressure needs to be monitored at full throttle, it should be steady in the high 40's psi. Check and let us know your results.

Also on the performance issue in addition to what Ian posted, when is the last time you changes out the HP fuel filter? These engines are very sensitive to that filter getting even partially clogged. Also, have you drained the VST lately? I drain mine every 100 hours when I pull 100-hour maintenance.

Thanks for both your recommendation’s. I will be back on the lake this weekend and will check all your ideas and let you know.