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xr400 carb sticky when running

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i have a 2003 XR400 that when the bike is not started the throttle works great. but when i start the bike and twist the throttle open some and let go it will not snap back to the idle position rather it stays at a high rpm. tore apart the throttle two or three times and cleaned everything and no luck. tonight i noticed that it has something to do with the carb when it is running the spring is not returning it to the idle stop but just a bit off.

can anyone help me with what to do next. maybe the bushings are worn or ??? Thanks for any help as i need this fixed so that i can ride!!!!

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I would start by lubricating the cable really well. You can even take the throttle tube housing apart and clean any dust/dirt in it.

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I would loosen the screws holding the throttle onto your bars and move the throttle out just a little. If the bike has fallen on the right side it will smash the throttle onto the bars causing it to stick -- been there, done that.

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When the throttle slide and the slide become a little worn, the manifold vacuum can hold the slide against the bore and cause the slide to hang up. Check the return spring tension, spring might be getting weak. Next time this happens, turn the throttle cable bracket by hand and see if that will return the slide to the idle position. You can check for cable binding and or throttle grip binding by removing the cables from the carb and check throttle operation by manually operating the throttle arm.

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thanks for the help guys..... i have cleaned the throttle at the bars very well and moved the throttle out and in and no help. when the bike is running i can rap the throttle and it will return to the idle position but if i am going down the street at a steady pace and let go of the throttle it will only return so far unless i twist the throttle back. could it just be some grim at the carb/spring location that need attention.

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Pull off the top of your carb. Pull the slide out. The slide may have some dirt on it which causes it to stick when it has mainfold vacum pressure holding it against the carb body. Clean everything really wel with carb cleaner. Lube the cables real well with a cable lube fitting while you have the carb slide off.

If you lube the cables while the slide is on the carb you can flush any dust or RUST from the cable housing down onto the slide which would give you the symptoms of your bike

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this sounds similar to my problem...does the carb stick at a higher rpm for around 10+ seconds then begin to come down? My did and then would die...I have cleaned the carb a million times and think it may be a bent needle...? I bought a new (used) carb and I am about to install that.

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i had the top of the carb off last night and it looked ok but i will do as you suggested and remove the slide and clean the heck out of it and reassemble. i also noticed that the cable looked like it may have been holding up things once the tank was removed. my bike will idle high and never come down as if it had a cruize control on it. kind of dangerous when we went up saddleback here in so. cal last weekend.

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