Adjusting carb, with picture.

[lyrikz74]

I have an 250ex i bought for my wife. I put a new plug, cleaned the foam air filter, and removed the baffle in the exhaust. It has some popping when letting off the throttle after full throttle. I know there is a screw on the carb that adjusts the idle, but isnt there one that you can richen up the fuel supply to an extent???

Is this the screw right here?

So, if that is the right screw to richen the fuel, how would i go about doing that? The bike is almost stock. I do not want to rejet the bike. Right now it idles great and runs great. I just know its running a bit lean. Any help?

http://img.photobucket.com/albums/v675/jcemerson/carb.jpg

[dukee66]

how do u know its leen?

[TRXRacer1]

That is the mixture screw but it only effects idle to 1/8 throttle. Before you play with that screw turn it in until it gently seats counting every turn. You need to know your base line is. Turn it back out to were it was plus a half turn more. See it that helps and adjust accordingly. Jetting is easy and cheap, burning up motors is not cheap so make sure that you're baffle removal didn't lean out the entire RPM range like it may have.

[lyrikz74]

Originally posted by TRXRacer1
That is the mixture screw but it only effects idle to 1/8 throttle. Before you play with that screw turn it in until it gently seats counting every turn. You need to know your base line is. Turn it back out to were it was plus a half turn more. See it that helps and adjust accordingly. Jetting is easy and cheap, burning up motors is not cheap so make sure that you're baffle removal didn't lean out the entire RPM range like it may have.

Ahh, ok. I thought that adjusting that would fatten it up the whole rpm range.

The carb is stock, never touched. Do i want to replace the main jet, or the bowl? All i did was just remove the baffle and it has a foam filter with the stock lid... Whats the baseline number for the jet thats in there now? 95?

[86 Quad R]

agree'd with the previous post but i'd like to add that you should check the mid rang and WOT aswell. you may need to richen up on the needle as well as the main jet.

[lyrikz74]

Originally posted by lyrikz74
Ahh, ok. I thought that adjusting that would fatten it up the whole rpm range.

The carb is stock, never touched. Do i want to replace the main jet, or the bowl? All i did was just remove the baffle and it has a foam filter with the stock lid... Whats the baseline number for the jet thats in there now? 95?

I talked to a pretty smart guy at jetsrus, and he states that i shouldnt touch the main jet. I should get a bigger pilot jet first and go from there.....

Any thoughts on that?

[86 Quad R]

address the pilot first then move on to the mid and top. ;)