I recently purchased a 2004 kx250f. I had it running fine, then when i get home the next day, i started it then warmed it up. At first it idled fine on choke, then i took it outside and about 2 min later took it off choke and throttled it and it would idle very high. Thoughts?? (P.S. i did try the idle screw and the bike is originaly from california)