Engine over revs and is slow to go to idle

[tex900ss]

I've recently acquired a Bandit 400. I cleaned the carbs, new battery, new tires, new fluids and now it is an awesome bike. The only problem is that when I adjust the idle speed to idle @1200 RPM, then the motor revs ridiculously high when I pull in the clutch to change gears. It will eventually get down to idle speed if I hold in the clutch about ten seconds. I can turn the idle screw down about a half of a turn and help the problem. A whole turn fixes it just right. But then the bike dies in a few seconds instead of idling.

To address this problem I gave the carbs another thorough cleaning. I have then tried adjusting the idle mixture screws. I have tried 1 turn, 1 1/2 turn, 2 turns, 2 1/2 turns and 3 turns. I think it likes 1 1/2 turns the best but it still has this problem. Also, the engine does not respond when I spray starter fluid around the carbs. I.E. no vacuum leaks.
 
I'm running stock jet sizes in what I think are stock carbs and engine. I put a piece of oiled Uni-Filter in place of the (missing) stock missing filter. Other than this revving/idle issue the bike runs flawlessly, pulling like a 600.

Any thoughts?

[gsxr400 racer]

get a air filter , mess with the fuel screws more after a carb sync

[tex900ss]

First, the Uni-filter that I used was recommended by my local motorcycle shop. He said it is just like what came stock. Is he wrong?

Then, after the carb sync like GSXR400 Racer suggested, it's all still the same(it does come on a little smother). The idle mixture screws seem to have very little effect on the problem. The only time the bike runs below 3000 rpm is if it sits for 10 or more seconds and finally drops down. If I lower the idle speed at all from this point, it dies quickly. The most annoying part is how the motor races when I am going through the gears. It will hit 9K between shifts. So now I ride constantly adjusting the idle speed - turning it up at a light and down as I drive.

I thought the sync would fix it. It sounded reasonable, but only one screw was a little bit off. I'm going to try some more adjustment on the mixture screws. Any other ideas?

Also, thanks for the help. I love these internet forums for bikes. If anyone needs any help with an old two-stroke maybe I can help.

[gsxr400 racer]

ok sounds like maybe a air leak or last but not least you valves maybe tight but unsure on that one.

[tex900ss]

It doesn't respond when I spray carb cleaner around the carbs. Should that rule out an air leak? I was thinking of checking the valves. I'm sure they're due.

More to come.

[gsxr400 racer]

yes as long as your sure you sprayed every where, carb boots etc... the only thing i can think of is your sure the rubber plugs are in the pilot holes and that the fuel screw orings areall there? I did have a 400ex honda 4 wheeler that responded like that and it turned out to be fuel screw was to rich. but it also seems like your getting raw fuel like the needle is too high or that you slides are sticking or you have a fraid throttle cable or a leaking choke assembly....