GS300L carb issue, revs slow coming down to idle when reving up.

[Guest]

Hi, I have an issue with the idle coming down from revving the engine. When the engine first starts it runs pretty good revs come down ok, as engine warms up the revs start hanging up taking longer to rev down. Carbs has been pulled and cleaned four times the first couple of times I found a sticky substance in the little throat screens (never seen these before on any Honda, this is my first Suzuki) that are in front of the throttle plates. I figured it was causing the slides to hang up, I thought maybe it was caused by the sea foam I had in the gas. I've never had this problem on all the carbs I've rebuilt. I've also never seen screens in front of the throttle plates before. So I cleaned both carbs, dumped the gas and flushed out the tank put in fresh gas, no sea foam, still have a slide hanging problem. I've checked for vacuum leaks around the intake manifold rubbers, slide covers and vacuum hoses, Suggestions?

[Nessism]

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