Machzzzz1
I used split fires in my Arctic Cats before and they were a piece of junk, though they were not the platiums, maybe that would make a difference.
mrZzz
Man you got me! It would hurt to try some Amsoil power foam - spray it into the carbs and then into the spark plug holes and let sit over nite, pull the plugs again and turn turn the engine, block up the rear end of the sled and rotate the track at several different rpm's, look at the plugs and the piston wash - after all you never stated what the piston wash was like ! There are so many things to start looking at - check you jet needles (e-clip position, are they held out with the retaining arm, are they bent, scratched) pilot jets are they plunged (just take a little piece of dirt) Float out of adjustment, air leak (air manifold or air box) do you have a DPM ? is it unpluged from the air box, blocked or split in one of the hoses to the DPM rail.
plugs take awhile to read and thats why you also need to look at your piston wash ! Klotz burns so clean that it will scare you looking at the plugs. look at your center carb seeing its black - float, jet needle, loose main jet, dirt in the pilot jet.
I think you rule out a oil pump adjustment, coolant would leave little very little droplets on the plugs, did you do a 1/4 throttle chop, mid range chop, wot chop ?
I hope this helped you some, with out seeing it I can only tell you what I wrote out on this forum to look at, good luck let me know what you find out.