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2004 CFR 450R unstable idle

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Just bought a 04 450r, has about 50 hours on it. Once started (hard to start though) it idles fast so I adjust the the fuel screw to slow the idle down, but after a few seconds the idle starts to creep up again so I adjust the fuel screw again and same thing happens. Any idea of why the idle is so unstable and what I need to do to fix it? Going through carb now, hopefully it helps.

Thanks.

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Worn FCR slide seal

Suco has rebuild kits available for this oft overlooked item.

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Just checked the Suco website....any idea of what model number i would need?

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you need to do your adjusting with the motor good and warm, after riding awhile. Most will need the choke to start cold, the idle will be low when you push it in, but it will creep up as the motor gets warm. THEN do your fuel screw adjusting.. Do a search, somewhere there is a good procedure for setting your fuel screw. Could be a partially clogged pilot screw as well. Gas with ethanol these days WILL gunk it up if the gas sits in there for more than a few weeks. With that few hours, it is very unlikely the slide seal is bad. my 04 has OVER 1000 hrs and i thought that was a problem with mine, it was not.

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I would look at the needle jet (the long jet the main jet screws into) , the needle wears it out and makes for the idle changing constantly , i fought this for weeks and was told about replacing it , $8 part and my bike idles again !

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I would look at the needle jet (the long jet the main jet screws into) , the needle wears it out and makes for the idle changing constantly , i fought this for weeks and was told about replacing it , $8 part and my bike idles again !

not with 50 hrs ..

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Thanks for all the tips...went through carb and there was some crap in it so i will see if that solves my problem

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Make sure your bike is good and warm when adjusting your idle. start it cold with the choke on and you will notice its idle will be low then slowly climb to your higher idle while choke is on. I normally leave my choke on for about 2 minutes or so WITHOUT REVING!!! the dang thing. make sure your carb is good and clean soak it in cleaner or seafoam for a couple hours and make sure that you are adjusting your idle adjust screw and not your fuel screw ;p. if your carb is all stock make sure you are in a location where that would come in to play and using fuel that would also affect such things. as in did you buy the bike in houston texas and now you are in Breckenridge colorado? i would start by setting your fuel screw (bottom of the fcr carb in a small hole) to the standard settings. once the bike is warm adjust your fuel screw until you hear the rpms even out. once your rpms on idle are even and sounds good thats when your fuel screw is right. other than that what i do is run the bike until it is warm then adjust idle low until it dies then give it a full turn high and let it idle. if it idles then give it a quarter turn higher and that is about where it should be. good luck and hope you solve your problem ;p

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will need to adjust both, but as posted a couple times.. need to do it with a motor that is fully warmed up and ridden around awhile. Just fyi too, the pilot jet has holes on the side as WELL as one down the middle. :busted: Ask me how i know now..

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not with 50 hrs ..

The about part is why four strokes need to come with hour meters from the factory but this will never happen as they want to sell parts.

If my friends are any indication my guess is the bike has more than double that.....time flies when we're having fun.

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The about part is why four strokes need to come with hour meters from the factory but this will never happen as they want to sell parts.

If my friends are any indication my guess is the bike has more than double that.....time flies when we're having fun.

50, 100.. even 200 hrs, the carb slide plate should not be close to worn out.

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