02 426 "Spawn of Satin" carb issues?

alright got an 02 yz426 wouldnt start,rebuilt carb and 2 jets were completely clogged. changed plug , new line, etc......and barely a fart from the bike..... massive compression...great spark.....and once in awhile...bra....ptttthhhh.....where to start first. first of all i really want to change cams to hot cams Stage 1 for auto decompress for obvious reasons...ie sore foot

So you know, "satan" is the devil. "Satin" is a tightly woven cotton cloth finished to a high sheen.

Anyway, start by checking your starting methodology against Doug Dubach's:

http://www.yamaha-motor.com/sport/4stroke_vid/4_stroke_vid_a.mpg

http://www.yamaha-motor.com/sport/4stroke_vid/4_stroke_vid_b.mpg

If that's not working, check the flywheel alignment by seeing if the TDC mark is actually at TDC (use a probe in the spark plug hole). Then check the cam timing, then install a fresh spark plug (the 426 fouls them easily).

If none of that gets you anywhere, go back to the carb, make sure that all the jets are 100% clear, that there's an O-ring on the fuel mixture screw, and that the screw is set to about 1 3/4 turns out as a starting point.

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