Just back from the track and disappointed as the problem still persists. What was done:
1. Track Shop (Authorized Rotax Service Center) rebuilt power-valve and changed bellows.
2. At track I adjusted throttle cable to make sure it was not “Over Opening”. I aligned it so the curved part of throttle slide is flush with the top of the carb at full throttle. I was sure this was the issue.
3. I checked to make sure there was no contact with suit, shoes, leg, arm with throttle cable.
Almost feels like there is excess fuel in the carb and when I let off of the throttle it needs a couple seconds to burn it off.
The other thing I noticed is some clanking/binding from clutch (New style). Could t be possible the clutch is not dis-enguaging and the momentiumn is keep revs up? I’m having the shop inspect the clutch as I am switching bock to a 12T driver fro 11T I am currently running.