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YFZ Carb Problems??

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I believe that My 07 YFZ is has a throttle that is sticking open. The only problem that i have with it is that it holds a high idle right after you hit the throttle. I looked the cable over and took off the cover on the carb to see and ensure that it is not the cable.With it running i used my finger to move the throttle. it idled high. i tried pushing the throttle closed didnt do anything.

Is there an adjustment that is off.

The shop Replaced the orignal carb with a new due to a problem. i don't know what that problem was. Yes they should fix this. but it was like 2 years ago and i dont think they will do it for free

Anyone have any ideas?

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Check the travel of the throttle cable cam on your carb. Maybe something is holding it. Was that cable ever replaced?

Is there a thumb screw adjstment on the carb? If so, try messing with that about 2 turns. Also try the air fuel mixture screw.

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where is the Fuel/air mixture screw? what is the approx. setting? with stock jet?

I dont know about the cable being replaced but it seems good. but i did order a new one. regardless

I removed the air box and noticed that there was oil from the filter in the tube to the carb so maybe there is that. sticking the carb up. so Im going to run cleaner through it tomorrow.

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First check the idle screw and make sure the cable adjustments(top of the carb and at the other end of the cable) are not holding the throttle open. If that doesn't work, take the carb off, leave the cable connected and look inside while you work the throttle in and out. Make sure that the slide closes all the way. If it has sat for a long while, then I would suggest cleaning the carb, some of the fuel could have gummed up partially blocking the jets, this would cause a lean condition and cause the machine to idle high. If that is the case, you need to fix it, lean is very bad.

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Has it done this since they put the new carb on? If none of the other ideas work for you get your service manual out and check to make sure the slide is in right (the slide is what is normally referred to as a butterfly on a older auto carb). I put mine together in a hurry after re-jetting once and I had one of the plates on my slide facing the wrong direction and it had the same symptoms

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