So i bought a 91 kx 500 for a pretty good deal and i'm trying to fix it up, well it has a keihin pj on it and i'm trying to get it jetted and find a choke plunger, it starts good, idles good and runs ok, but when your crusing in a gear and try to accelerate it surges and misses but if you shift up a gear and gas it, it pulls good and clean all the way to redline, i pulled a plug and it was alittle brown but not bad, it has a 165 main, a 55 pilot and the needle is in the 2ed from the bottom, air screw is 1.5 turns out so any input would be greatly appreciated, also i needs a choke plunger cuz the plastic handle is broke, i went to the kawasaki dealer and tried to get one, but there a little slow there and had no clue witch one went for a pj they keep trying to sell me one for the carb that came on that bike with is a pwk i think? so if you know a part number or any thing that would be great, thanks!!!