2000 IS carburetor problem, help?

[Iswing]

I purchased a 2000 IS and it had cobra exhaust system, which came off as soon I got home.  The owner said the carburetors were rejeted for the cobra exhaust system.  I removed carbs and put in standard main and low speed jets.  Reinstalled them and now it will not idle at all and acts like it's getting no gas.  Have to turn throttle a lot to keep it going.  Any ideas?  Thanks

[sandy]

Check/adjust the pilot screws. They should be set to 2 to 2 1/2 turns out from lightly seated. Also, there’s an idle adjuster on the right side between the #1 and #3 carb.

[Foozle]

I purchased a 2000 IS and it had cobra exhaust system, which came off as soon I got home.  The owner said the carburetors were rejeted for the cobra exhaust system.  I removed carbs and put in standard main and low speed jets.  Reinstalled them and now it will not idle at all and acts like it's getting no gas.  Have to turn throttle a lot to keep it going.  Any ideas?  Thanks

So were the jets you removed and replaced NOT factory (35/100) jets?  I ask because Cobra pipes don't require re-jetting.  Instead, the Cobra kit comes with new needles - which are adjustable and (I believe) more tapered than OEM.  The standard Valkyrie carburetor needles are not adjustable. When I swapped out my Cobras for glass packs, I experienced a severely lean condition.  Setting everything back to factory specs (including needles) seemed to do the trick.  As always, YMMV.

Terry