Air Mixture screw???

[thumper250x]

Is this the idle screw???or what and where is it..

[KY Woods Rider]

No, the idle screw and pilot screw (AKA air/fuel mixture screw) are two completely different things.

The pilot screw is located near the front of the carb, on the bottom, pointing directly downward. If you are looking from the left side (shifter side) of the quad, the pilot screw will be partially hidden behind the metal bracket that holds the idle adjuster. The easiest way to find it is to look where the front of the carb goes into the intake boot, then look a bit lower on the main carb body, there will be a little round portion of the carb pointing straight downward with a little gold flathead screw in it. That little gold flathead screw is the pilot screw.

[thumper250x]

So should i have that completely tight in there or turn it out 2 1/2 turns??

[KY Woods Rider]

Never fully tighten a pilot screw. When making adjustments you usually have to turn it all the way in and then count the number of revolutions as you back it out. However, as you're screwing it in, go slowly and as soon as you feel it lightly bottom out, quit turning it. Then back it out the desired number of revolutions.

The exact number of revolutions that it needs to be backed out will depend on the size of your pilot jet and the quad's set-up. If you have the correct size pilot jet in your carb to suit your quad's modifications, then you should need a setting somewhere between 2 and 3 turns out, with the most common setting being approximately 2.5 turns out.

[cals400ex]

the fuel skrew on a 400ex will be on the very bottom of the carb, not the side. it is a bronze colored skrew you turn with a flat blade skrewdriver. the idle adjustment is on the left side of the carb when sitting on the bike. it is a silver skrew you can turn with a flat blade or your hand. it is a little knob with a little black hose connected to it.

[thumper250x]

It wont fall out if its not fully tightened??? thanx alot for the help...

[sevens]

Yes, you should never over tighten this screw, turn until it lightly seats. Turning it more could damage the seat.. I've had mine as much as 4 turns out and it never fell out, its spring loaded :D