RE: YS engine problems
Yes, it it best to set everything to factory settings, and that's 1.5 turns out for both the low end and the high speed needle valve, with the regulator flush with the casing as stated by Flyboy Dave above. Try Powermaster YS 20/20 instead of CP 15%. Also should you need to lean out the low end, then the low speed screw should be turned "counter clockwise".