I’ve see responses to this issue before online, but now cannot locate them, so…

Once my ’09 450 Griz is warmed up, it will not take much of a throttle before bogging down, only reaching 11-19 mph. It’s used with about 2,900 miles, and had ran great for the past year. Now it fits right up and idles fine.

What I know:
Air filter is clean;
Gas flows into carb freely;
Gas is clean;
The Griz has been ridden frequently and has not been sitting for extended periods.

What I’ve heard:
Carb problems, dirty electrical connections, faulty limiter.

It seems this is a common problem, but I have not heard the solution. And go!