Yamaha xs 360/400 hangs when turning up and goes off idle

Hello dear Yamaha friends After changing the piston rings, new capacitors and ignition coils my xs 360 runs quite well again.There are only 2 problems, maybe someone had similar or has an idea what it might be. 1) If I turn up, it hangs on about 6500/7000Tours.In this “hole” it hangs so about 5 seconds, then it turns Hurtig further to the red area.Could it lie on the fly force adjuster ?? And if yes,how do you notice wear or defects there ?? 2.Si After 15-20 sec .sometimes even after a minute it goes off abruptly, without misignition or similar, it just stops as if you had turned off.Of course, it usually goes off exactly when the traffic light just turns green-especially nerfig. I have already turned out the idle mixing screws further, but does not bring anything.If you turn up the stop knurling screw on approx. 2000 tours, it goes then but then it runs 20 sec on 3 or 4000 Tours until the speed goes down to 2000 and motor brake and switching is not really good, because the speed stays too high for the first time. Has an idea on the topic “Hanging and going out in empty run.Bin grateful for every tip Greeting Paul