Stuck on high RPM

Hey all i got a 2004 yz450f and it starts fine but when i gun it the bike seems to get stuck on high idle for about 5 to 10 seconds. Even after it warms up. Some times the only way to get it back down to idle is to mess with the idle screw. I checked the exhaust for leaks and did find any that i can see. Cleaned the carb and still the bike gets stuck. When im riding the bike its does the same thing but im in gear so that slows the rpm down. Any ideas?

either of these 3 things. Esp if you had the carb off

1. Throttle slide plate is on upside down. Flat side goes down.

2.Throttle slide vacuum seal is on backwards or damaged.

3. Pilot circut is clogged. This usually is accompanied by a red exhaust pipe VERY fast and or low rpm idling problems

Is your throtle cable boogered up and holding the throtle open, try cleaning the cable

or try adjusting the idle down and check the pilot screw adjustment

Sweet! I did everything but check the valve space and it worked.. not sure what worked but it worked. Thanks guys!

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