These older carbed bikes may run like that if they sit for a period (2-4 months). With my experiences, the needle valves on these bikes tend to fail. Once you get it running, it will continue to run very well, that is, until you let it sit for another 2-4 months.
At some point in time, I will replace all four of the needle valves and the needle valve seats. At this point in time, my bike runs perfect, so no need at this time (I have stuff going on right now). As long as I ride at least once or twice a month, no problemo's.
When the Needle valve/Needle valve seat fails, fuel will flood the carburetors. When this happens, it will run very poorly, if at all. Also when this happens, fuel will gush out of the overflow hose.
I have 24k miles on my bike, and still have the original plugs. They are in 'like new' condition, no need to change them. I have checked them, cleaned them and re-installed them.
The pilot jets are inside the float chamber with the needle valves, so they can be serviced at the same time.
Just a suggestion; I have had very good results using the Chevron with Techron fuel injector cleaner.
Tony
