]Last week I started my 2003 Yamaha bear tracker 250 after sitting for about 1 month. It ran fine when I parked it. When I started it up and wentvto give it gas it started to spit and sputter. Then it bogged out and shut off. My buddy cleaned the carburetor out for me reinstalled an it still does it. I was reading on other places that if cdi box is going bad it won't let you rev it up. Could that be my problem

 

Chances are a quick clean on your carb is not enough... A complete rebuild with a proper kit is the only way to do it. A quick clean usually pushes the dirt further into the tiny holes and makes things worse. Also check the rubber boot between the carb and head, if these get a crack in them form age or a hole, it will cause what you describe. The CDI box is a mabey but if it was running good before then more likely a fuel issue. Disconnect fuel line from carb and see if you have good fuel flow from tank, there is also a drain on the bottom of the carb, open it and see if you have fuel flow thru the carb.

 

Ok so I pulled it all apart again left everything out and sprayed all hole clean with carburetor cleaner blew air threw and sprayed it again. Float is working good and I have good fuel flow. I replaced the intake boot. It's still doing it. It does idle fine takes a little to get it to start now. But when I give it full throttle right away it still spits and sputters.

 

Is the air box sealed onto the carb? Airbox is needed for proper air flow thru the carb. Sometimes some grease is added to all joints to help seal and keep dirt out and that includes the rubber intake. I hate to say this but just taking a carb apart and cleaning it, then reassembling it does not frequently work, usually the gaskets need to be replaced as well thus the rebuild kit requirement. Are you sure the float level is set correctly? This can be very critical! I am not ruling out the cd box, that is still a possibility but it still sounds like a carb problem or an air leak. I can tell you that the carb is set lean from the factory, so any air leak or not having the airbox installed correctly will cause the same situation. Difficult to diagnose over a computer...lol..

 

How do I know if float is set correctly also could it be the air an fuel needle needs turned out some more.it does run better just still a little sluggish when hitting the throttle I'm wondering if there could be water in my gas

 

Now adays you can get water in the fuel anyplace you buy gas. I would drain the fuel and look at it closely just to be safe. If the carb has been rebuilt then the air adjustment screw needs to be adjusted for optimum performance. If you use a good carb rebuilding kit the specs for the float will be in the instructions. I had a factory service manual when I had mine which had all the specs but sold it with the machine. If your planning on keeping your machine you might invest in one...it has all you need to know!!