250 2009 yz250

ok guys i'm stuck on this one. i have a 2009 yz250, just put in a new crank and carb with wiseco reed intake and new air filter. the bike starts fine and runs great with the choke on. soon as i have it warmed up and take the choke off it starts to bog at lower rpm and wont idle. i can keep it running with the revs up. with the choke on it runs perfect. got a 178 main and a 50 pilot, needle is on second clip from top. air screw is 1 turn out. running 97 pump gas with maxima 927 at 40:1.


Staff member
Did you clean the carburetor idle circuit? A clogged idle passage will give those symptoms.
50 idle jet is already quite large, you should be able to get it to idle with the air screw between 1 and 3 turns out from lightly seated.
-BIG DAN:thumb: