I decided to prioritize fun over frustration. I haven't really been able to ride since the head gasket and piston problems 4 years ago, and I've put endless hours into this. So now I am going ride the bike and have FUN at least one hour for every hour of trying to fix whatever is still wrong. I've taken it on three 15 mile rides now, and each time it runs great except for the idle issue. After my most recent synch and cable adjustment it is running as well or better than ever, as long as its moving. It is peppy and very fun. I have several more fun rides ahead of me before I try to find the problem again. Currently it is still:
hard to start, and won't start with choke at 70-75 degrees FIt will usually start quickly but baaaaaaarely, and then dies in a second. I have to start it multiple to many times, each time it will run a fraction of a second longer before it dies, until eventually it stays running. Once it is running I have to give it some choke for a minute to keep the idle up.
Once it warms up it rides great, and will often idle stable at 2500 rpm at stops, which is obviously too high, but its better than dying. But sometimes it will just die if I don't stay on the throttle at stops. I've tested for air leaks over and over and find none. I've read that tight valves can cause some of these symptoms. I know they are set to spec, but whether they are worn or something I do not know. Should I check them hot? I considered buying vacuum tester for a better synch but I think I'd have to drill something out to even hook them up so I'm not rushing to do that.
Not sure what to do next, but further suggestions appreciated. I'm just gonna ride and have fun. If it blows up it blows up, at least I will have had my fun.