Just finished installing on my 2004 and I went with the needle clip at default groove #2, 142 main with no extra washers under the clip and idle mixture screw at two turns. WOW, what a difference. Also changed my front sprocket to a 16 tooth at the same time. I was worried about losing some take off power but the jetting offset the sprocket. And my temp used to run around the middle of the gauge and the fan would kick on when I came to a stop on a warm day, now it runs a full quarter back and the fan hasn't kicked on since. Very happy, now I need to install my torsion spring Doohickey kit that I ordered from Mike before the jet kit. Thanks, Mike!