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Turn right or lean the bike right and it goes rich?!?!

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I recently let ethanol gas sit in the bike for some time. Needless to say when i went to start it to get it ready to ride again, it wouldn't start. I took the carb and cleaned it good (the right way, no tip cleaners through the jets or anything). I got it back together and it ran good. It wouldn't open up all the way due to being too rich. I figured at this point my float height is off so I took it back apart....set the float height to spec in my manual, put it back together and tried again. Opens up, runs great, fast and powerful as ever until you take a sharp right turn and really lean the bike then it goes way rich again...almost to the point of choking out. It doesn't do this when turning left. I made sure the carb was level and even turned it back and forth testing it to see if I could find a happy spot but no difference. So when I turn right and really lean it over it goes way fat.....!!! Any suggestions...greatly appreciated.

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i would have suggested float height but you say you adjusted it,maybe you should adjusted a bit lower and have less fuel in the bowl.I'm guessing when you lean it the way it runs ok the gas comes out the overflow and not in the engine.Also check your reeds they may not be sealing proper.

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I would also check your needle valve as well. The valve has a viton tip, which acts as a sealer which stops the fuel from flowing into the bowl of the carb.

Also hows your top end? hows compression?

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i would have suggested float height but you say you adjusted it,maybe you should adjusted a bit lower and have less fuel in the bowl.I'm guessing when you lean it the way it runs ok the gas comes out the overflow and not in the engine.Also check your reeds they may not be sealing proper.

I will try to adjust the floats a little lower this evening and see if it makes a difference. I checked the reeds yesterday...everything looks great nothing damaged or out of place. Thanks for the input!

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I would also check your needle valve as well. The valve has a viton tip, which acts as a sealer which stops the fuel from flowing into the bowl of the carb.

Also hows your top end? hows compression?

I've checked the needle valve 4 or 5 times. I swear the bike is an 07 and i've put some time on it and the viton tip still looks new. The seat also shows no signs of damage. I've tried the hose on the fuel inlet and blowing into it. Turn the carb over and it stops my breath so I think everything is good there. Fuel doesn't run out of the overflow all the time so I was kinda eliminating that possibility.

As for compression, it's a shin getter. It likes to kick back.......Hard. Haha. Compression is good.

Thanks for the help!

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Think we might be onto something. Dropped the float level out of spec by about 1 mm. Spec is 5.5 to 7.5mm. Went closer to 8.5 mm and there is a big improvement. Didn't get to ride it because it was dark but just running the engine and leaning the bike it acts a lot better. Plug is tan in color. Dropping the float out of spec like that to correct a rich symptom......Does this mean my jetting is off?? It has never been touched until this problem, bought the bike brand new in 07. Would the dealer who assembled and tuned the bike have compensated too rich jetting by adjusting the float height??

Kinda odd considering the bike has always had tons of power, ran perfect, and never fouled plugs till this little ordeal. I run champion plugs and Klotz rc50 @ 40:1

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Theres a number of things that can affect your jetting. Like weather is a big part, thats why 2 strokes can be very sensitive to weather changes.

Alslike i said a worn top end can make your bike run rich, reeds, etc etc, there are so many factors. but since you have a tan color, thats a good sign, but i would ride it and test it out haha

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1mm isn't much and maybe you didn't do it corectly at the first try.Just an assumption on trying to explain why stock setting didn't work proper for you.Glad its working better now.

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1mm isn't much and maybe you didn't do it corectly at the first try.Just an assumption on trying to explain why stock setting didn't work proper for you.Glad its working better now.

Hope you're right. I don't work on dirt bikes much. I was hoping not to back in 07 when I bought a new one. I always had used bikes before and was tired of wrenching instead of riding. I got it out and rode it today. It still goes rich on a slow right turn ( more less sliding to a stop and making a right turn by spinning around with the bike leaned over) but it isn't nearly as bad as what it was. it's cold here too. Perhaps the weather is throwing my jetting off a bit also. I'll keep an eye on the plug and take it riding here in a few days and see how it does. I'll be sure to follow up if it does good. Thanks guys

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Since it is cold there, if anything your bike should be running leaner, not richer.

I just went through a similar thing with my 2006 YZ250 where it would run great but as soon as I would hit bumps or G it out into a berm it would go rich, load up and sputter badly. I also messed around with the float level and it seemed to provide relief like you've said but you are really just masking the problem by compensating for a rich condition by leaning your float level.

Look at your starter jet. It's the tall brass tube in front of your pilot jet. Make sure it is clean and blown out all the way up to the little hole in the throat of the carb. It is a very tiny hole and gets clogged up easily by any corrosion or gunk in the carb.

Another suspect thing from gas sitting in the carb that can cause these symptoms is the O-rings under the jet block. The jet block is the assembly in the bottom of the carb that houses the main jet and pilot jet. It has some torx screws that hold it to the main body of the carb. Between the jet block and the main body are some small O-rings. Old gas can deteriorate these o-rings and then the bike will suck extra fuel there when leaned or under G-load.

Also, your float needle might be sticking. Take some Brasso and Q-tips and clean the needle seat out really well. Make sure the needle is nice and free in there.

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Since it is cold there, if anything your bike should be running leaner, not richer.

I just went through a similar thing with my 2006 YZ250 where it would run great but as soon as I would hit bumps or G it out into a berm it would go rich, load up and sputter badly. I also messed around with the float level and it seemed to provide relief like you've said but you are really just masking the problem by compensating for a rich condition by leaning your float level.

Look at your starter jet. It's the tall brass tube in front of your pilot jet. Make sure it is clean and blown out all the way up to the little hole in the throat of the carb. It is a very tiny hole and gets clogged up easily by any corrosion or gunk in the carb.

Another suspect thing from gas sitting in the carb that can cause these symptoms is the O-rings under the jet block. The jet block is the assembly in the bottom of the carb that houses the main jet and pilot jet. It has some torx screws that hold it to the main body of the carb. Between the jet block and the main body are some small O-rings. Old gas can deteriorate these o-rings and then the bike will suck extra fuel there when leaned or under G-load.

Also, your float needle might be sticking. Take some Brasso and Q-tips and clean the needle seat out really well. Make sure the needle is nice and free in there.

ok i know all the jets are clean. I can spray carb cleaner through each and see where it comes out. When i soaked the carb i did remove the jet block and when i put it back didn't have that seal so i just used the old one. Where could i find this seal....Thanks!

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