running rich. carb adjustment

My 2005 kx 125 is running to rich. Spitting black mist out of tail pipe. Took out the plug and it is wet and black. Where at on the carb do I adjust the air/fuel ratio. And how do I go about doing this. Any tips/info would be greatly appreciated. I have main jets 420, pilot is 20. Have a pro circuit pipe and racing muffler. I just rebuilt the engine piston, rings, and crankshaft. Rode it about 7 hours. Its really rough in the beginning smoking and spraying realy bad but after I ride it and work it through the gears it runs good. I also have a v force reed valve set up

If you are spitting out that much spooge, you either have a right hand crank seal needing replaced, or you need to do some serious jetting adjustments. The air screw isn't going to fix it. Check out Pro Circuits recommended jetting for your bike. That should give you a good base to work with. I believe PC's jetting specs are based on sea level around 70*.

Stock Jetting: Main: 420 Pilot: 40 Needle: 6CHJ10-82 Needle Pos: 3 Air Screw: 2 1/2 turns Slide: 5.75 (not familiar with this)

PC Jetting: Main: 400 Pilot: 35 Needle: 6CHJ10-82 Needle Pos: 2 Air Screw: 1 1/2 turns

I don't think it would be the crank seal since I had A mechanic put in the new crank. And I put in the correct jets recommended by pro circuit I just went to the site to look what they were since I forget so I may have list the stock ones by mistake.

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