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Kill 4 jetting advice on a 99 cr250

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Friend of mine has a 1999 Cr250 (2 Stroke). I cant take watching him try to jet this bike anymore.. Any suggestions on a main, pilot and needle position to give him a base to start at? he has been told so many different things by the voices in his head, he doesnt know wich way is up anymore.. He has stock motor, 40:1 redline, v force3, procircuit pipe, 100 degrees in Vegas, 3000 feet. PLEASE HELP ME HELP HIM!!!! The bike stumbles on its face when it is gassed hard (off idle). Has a real deep sound to it when it is doing this.. sounds as if someones hand is over the intake on the carb.

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what is his current jetting?sounds like the pilot jet is way to rich or the power valve isnt working.

has he had the cylinder off?

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no cylider off... compression test is reading 180 @2500 above sea level.. when pipe was off couldnt see any black below piston rings...current jetting is 180 main, 45 pilot, stock needle (1370) 2nd position, airscrew 2 turns out, running 40:1 @100 degrees outside temperature..

not my bike so i dont know the ins and outs of his so i am limited to what i have seen for the last 7 rides with him... He has messed around with the jetting so much he doesnt know wich way is up.... like an idiot he never wrote down what was in there in the terms of jet sizes before he started messing with it... now he cant go back to how it was before he started... he has tried back at stock #'s (main 190 pilot 42) but it didnt reach its potential... He Claims that it is better after it warms up...

1st start in the morning it took 15 kicks to get it started... so we changed the pilot to a 45 now it starts easier 3-5 kicks but at 1/4-full throttle bursts its sucks butt and bogs like it is stuck in a vaccum chamber (real Deep sounding)

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there is a inspection cap on the left side of the cylinder.remove it.start the motor and rev it.make sure the power valve shaft turns from L to H when it revs.

if thats ok,have him close the air screw fully.if its better go to the next size richer pilot jet.

move the needle to clip 3 as well.

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