I have a 2010 Sportsman 90 that will not run smoothly at much more than a barely cracked throttle. I took it to the shop twice. The first time, a rebuild kit was put in the carb. A new sparkplug and misc maintenance. I picked it up, brought it home and found they had adjusted the throttle stop back to the factory setting of "very restricted". The kids rode it that afternoon and the next day asked me to speed it back up. I backed out the screw and it ran like it did before I took it to the shop. I returned it to the shop within a week. They put in another rebuild kit and when i picked it up, I asked if they adjusted the throttle stop. They had, and told me that the throttle stop was the problem all along. They said the 90 was intended to run at a very resticted throttle setting. And that if I adjusted it back out, it would allow the carb slide to move too far and flood the carb. The engine does run like it is flooding or choked when you push the throttle past a point. This does not make sense to me. It ran for years with the throttle stop backed out. Does anyone have any experience with this? What else could be the problem? Sorry for the long post
Ride With Joel Hetrick at Loretta Lynn’s en Route to the 2017 ATV National Championship