thought I answered this already,,,??? Classic "brass kit" symptom! >>> You need a "brass kit".. this is the needle jet
and the jet needle
in the center of the carb. The jet needle is the thin needle that hangs down from the center of the slide... The needle jet is the "hole" that the jet needle slides into...Remove the carb, take the bowl off, remove the main jet, the needle jet holder should be able to be gently tapped out, the needle jet is a short brasspiece,, it comes out through the hole where the slide goes,,, reinstall the NEW needle jet, needle jet holder...(it may have a groove in it for correct location). once its seated, you can reinstall the main jet..NOW >> to install a new jet needle,,, remove the slide from the carb.. remove the spring and seat from the slide that holds the needle jet in place.. NOTE which groove the clip is in on the old needle.... (should be the middle one). re install the new needle, reinstall everything else and your atv WILL run fine for a long time..This is a common problem on ATV's..
you need part #'s
1990 Kawasaki BAYOU 300 4X4 KLF300 C2 Carburetor