What jetting should I run

I have a 2001 yz250f. Stage one hot cams full FMF pipe twin-air air filter think that's all. I really have no clue what jets to run in it. I run 92-93 octane in it. If any of you could help that'd be much appreciated. Thanks.

What problem are you having? That is more important than any blind reccomendation.

Only time it will run is with the choke on but the idle is really high as soon as I turn the idle off it shuts off

Clean the carb

Buy a brand new pilot jet and install it, same size as is currently in the bike

Make sure the spring/washer/oring are on the fuel screw, set it at 1.75 turns from gently closed and ine adjust when the bike is hot.

What main should I run it had a 190 in it. I put a 185 in it today seemed to work but idk

What main should I run it had a 190 in it. I put a 185 in it today seemed to work but idk

what needle is in the bike? the reason I ask is the OEM needle for that model needed about a 170-178 needle. If the previous owner installed a JD Jet Kit needle, that needle used a 185 needle.

Like william1 said, clean the carb and change the pilot jet. The main jet doesn't affect idle.

Edited by oldnbold

Ok I got the bike to idle good, but when I'm riding I hit the gas and it bogs never happened before. Know anything?

You put the AP spring in the diaphragm housing on the wrong side.

What ap spring?

...or you lost it. The AP pump has a spring in it, It belongs in the cover side. Look at the parts fiche.

Never pulled the ap spring. Off its still there it still bogs and its kinda hard to start

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