So like a month ago, I cleaned the carb on my yellow 400. Nothing was changed, just cleaned. Slide moves freely. When I reinstalled it, it had a wicked stumble around 3500 RPM. I dropped the needle 4 settings and it helped, but it still did it. I cleaned the air filter, and it does it even less. Am I on the right track? It sounds like it hits rev limiter, then it’ll rev up. Most of the time it’ll run fine now but it’ll still stumble 20% of the time.