I remember this on my buggy. Unfortunately I don't what fixed the problem. I decided to go through everthing cause I was tired of my buggy trying to do a backflip when I was letting off of the throttle. Someone suggested the engine had an air leak or lean condition. So I tore the carb down, cleaned it up, and sealed up the engine and carb. Another person said that my linkages weren't lined up properly. This person mention having the same problem on his Mugen. So I loosened everything up, removed the servo horn, adjusted the carb angle, adjusted the linkage collars till everything looked perfectly straight and aligned, no binding or catching. I did all this at one time so I'm not sure what fixed the issue but I have not had this happen with the T yet. But I learned from the 8B so setting up the T was no problem.