lose the pitts muffler if possible.. had one on my .46 wouldnt run worth crap.. took it off ran fine.. plus maybe tune it up if that dont work.. with the throttle halfway open.. screw the second needle in to about 1/16 of the spraybar and tweek from there .. had to do that also.. os instructions are wrong. took the motor to the lhs here and the german guy tuned it up in 30 seconds... runs like a champ again..
just a thought