Dirty intake port/valves

[kat_pilot750]

While figuring out the cause for a bad misfire + bogging after 1/3 throttle/ 4K rpm, I took a gander at the intake port to look at the intake valves and saw brown/rust colored discoloration and some of the intake valves looked dirty. Before it sat for a while, the tank had a fair amount of rust in it which bunked up the fuel filter and carbs. I've since repealed the tank with por 15 new fuel lines and cleaned carbs. Is there a way to clean the intake ports and valves without taking off the cylinder head and pulling the valves, like using carb cleaner? Also, could that be the cause of the misfire \ bogging under acceleration? Im also investigating a suspected vacuum leak, looking at the carbs, and doing a valve clearance check today as well. But I figure while I have everything apart may as well investigate this avenue. I'd post pics but don't see the "attach file" option and I don't have a photo site account.

[92xjunker]

Not advisable, as the crap you clean off will end up in the cylinder. The best way would be to remove the head. If you're bent on doing it with the head on the motor, you need to figure away to put a vacuum source in there while you do it and ensure the valve is closed then flush the port.