i am totally pissed off at the minute.ive just fitted a mallosi kit,210cc,to my p2oo.i havent touched the casings but just done the head etc.its got an sip performance on it.i set it up as the mallosi instructions said and it was totally crap!Tick over was o.k. & first few revs not to bad ,but get to the middle of revs and it would not have it,it just jutters!.Any way i`ve reduced the main jet to a 128 & it was a little better.i have also changed air corrector to BE4 & now its got a BE5 in it with the 128 main jet & the 160 air jet(?)Its still very dodgy in mid revs although i can just get it to rev through.WHAT MUST I DO TO GET IT TO REV THROUGH THE RANGE SMOOTHLY WITH THIS MID RANGE PROBLEM??? HOPE SOMEONE CAN HELP ME OUT WITH SOME TIPS.THANKS DEANO,BBSC.
[:D] A mate of mine had this problem. I fixed it for him by fitting a 155 or 158 air jet, a BE5 and a 125 main push jet. This seemed to help it out alot. Also have you thought about changing the spark plug to something a little hotter running. The only other problem i could think of that could do that is that the main air mixture screw in the rear of the carb ( the one that you get at through the back of the carb box ) may need adjusted because of the big pipe. You might want to try a 1/4 turn in either direction to see if that helps.
Hope one of these suggestions will help you out.[:D]