Carb, carb, or the carb. Sometimes its just as easy as tracking down the correct auto-parts-store rebuild kit and only replacing the accelerator pump (short dowel with leather and spring seal) and tuning the A/F mixture with an exhaust gas analyzer...most good Honda shops should have no problem tuning the carb for you at a very reasonable cost.
The SeaFoam Experiment is often used as a gigantic catch-all band-aid that usually cures most carb-related problems, assuming the carb and its internals are good. A good de-gunking never hurts, but if the carb is not adjusted properly then you are swimming against the current.
Make sure and double-check that all of your vacuum lines are connected, and to their correct locations. We used to go over each connection with the diagram, then zip-tie (the little black ones) each hose in the right spot...if you've ever owned a Mazda Rotary-powered car, you are well-familiar with this concept.
Also make sure that BOTH fuel filters have been replaced....one "primary" at the fuel tank, and the small "secondary" just after the mechanical fuel pump (located on the engine). The little one at the motor almost never gets changed, and can show up as apparent fuel-starve conditions.
That should keep you busy, and probably out no more than $12 with the SeaFoam, zip-ties, and both filters. Good luck!
-JamesW
Suzuki tagged a valve :-( bad noises, bad!