Stalling Issues

[Old School]

Today I replaced the plug, had to re-tap for it. Changed the oil. Of course in all this to make things easier I took the tank off for the spark plug. I worked out the high idle issue so I thought. Now when I start it up it seems to idle at a more normal rpm, still a little higher but much better. The issue I am having now is that it runs good even under a revved condition it will stall shortly after starting it. I had it out the other day and did 90 mile on it with no problems. Now I do some routine maint and I get this. I have searched other stalling threads and the only thing I can figure is that I have a vacuum issue that is keeping it from getting consistent fuel???? In the process of all this I checked the air filter and it looks good. I also opened up the carb and it looks clean and the throttle area responds correctly and the plunger moves freely. I am at a loss. I put the new plug in gapped at factory. NGK. Oil level is measuring correctly. Thanks and I hope I can get some help with this. I am starting to wish I had done nothing but just ride it w/o maint.