Depending on your altitude and temp. you might need to change your pilot jet and play with air screw. I have a '99 220 with same pipe and mods, going leaner on the pilot jet made a big diff. I ride between 5000' and 8500' in the summer with temp 85-95 deg. I am currently running #40 pilot, clip 3 down, #142 main, air screw 1 1/4 out. I tried the clip 2 down, but lost power both @ low end & mid range. Once you have the correct pilot jet, 1/4 turn on A.S. makes a big diff from idle to 1/8 throttle. This jetting runs a little fat at higher altitude, but still makes good power & I still have a margin of safety for cool days &/or high humidity.