I 2nd the float bowl levels. Pull the bowls and gaskets and with the carbs upside down, measure the distance between the float and the carb where the gasket would be. It should be 21mm. Hopefully that helps.
I 2nd the stacks. Put some diesel in there and some redline cetane booster and that fucking boost bottle will put you on your ass in a heartbeat. NO SHIT!
pull your carbs apart and clean them thoroghly. Make sure you blow out the pilot jet also. Make sure those babies are in sync. Also, float adjustments are important while your in there.Thats a do it yourselfer right there.
So it runs good at WOT? Wheres the bog? Low,mid? Hows the plugs look? Stock filter? Remove the lid and run just dont go through dirt and see if the bog goes away.