2003 KX250 Ball park jetting????

I got a 2003 KX 250 and so far it dosn't seem to want to idle. I starts up first or second kick cold and goes good with the choke on but its deffinatly running rich. The plug is oily and black sooty looking. The jets are a 160 needle and 48 main jet (or did I get those backwards ?). I dont know where the needle is set yet or the fuel screw.

Anyways I need ball park figures for running in sea level in california between 40 and 50 degrees and running 40:1 mix. Thanks!

Have you tried adjusting your airscrew out and see if it improves(make sure you turn it in until lightly seated and count the turns so you know where your baseline setting was at), if it gets better the more you turn it out and you end up at more than 21/2turns out you need a smaller pilot jet

If the bike is in good mechancal condition(good topend, reeds, etc) if its worn you'll be chasing your tail as the worn motor will constantly be changeing

This is stock KX250 165main, 52pilot, NAFH jet needle on the 2ND clip position, airscrew 2 turns out

This is Pro Circuit's recommended jetting 162main, 50pilot, NAFGjet needle on the 2NDclip position airscrew 1 1/2 turns out

i think pro circui suggest for their factory racers

go 158 main and 45 pilot on 2nd clip.

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