moved that post /\ from the other thread.
IMO.....you gotta get the #6 slide, the amount of air the slide lets pass thru the carb effects the amount available to the airscrew circut,
if the #4 slide is letting less air pass thru than the #6, thats less air available to pass thru the airscrew circut.
your 2-1/2 turns out to achieve high idle when tuning the airscrew/pilot circut, suggests you need a smaller pilot, thats due to the less air passing thru the #4 slide and airscrew circut ?
now that may not be a problem to go smaller, as long as the rpm's are not hanging when revved, and airscrew turns to achieve highest idle is under 2-1/2 turns, as you are matching the pilot to the air passing thru to create the proper air/fuel ratio, less air requires less fuel.
go smaller pilot as it is telling you too, or get the #6 slide.
re-read the tuning airscrew DIY and follow it exactly, the turns out tells you what it wants....
http://www.blasterforum.com/threads/adjusting-your-airscrew-pilot-jet.51060/
for the record, I had a mx race team mechanic tell me they run 38 pilots
I run a 48 at 1.5 turns out for highest idle @ 1800'+ elevation
as mentioned before, check that the idle screw is actually raising the slide.
my PJ does not have an idle screw so I too have to use the cable to raise the slide, I feel no ill effects of doing so except the idle increases very slightly when the bars are cranked to the right.
I'd be willing to bet carb parts warehouse can beat your dealers price on a #6 slide ?
http://www.carbparts.com/keihin/pwk33_39parts.htm
