idle adjustment...HELP!!!!

[Mercedes]

I friend played with my idle adjustment scew on the carb, and I would like to put it back to original setting(I did not move it since stock 06').

I just pulled off Curtis Sparks and K&N and rejetted it to stock for winter.

Wanna be sure I'm not getting to much gas and washing my cylinders..

So whats the best way to readjust the idle????

HELP PLEASE....

[the Z Man]

Should be a black thumb screw under your carb, adjust as desired, Z.

[Mercedes]

What do you mean???? Wont to much gas be very bad for my engine???

There should be a proper idle setting !!!!!

[GPracer2500]

Adjusting your idle speed shouldn't cause cylinder wash. The idle speed adjustment doesn't have anything to do with the a/f mixture. It's just a throttle stop screw. Adjust it until the idle speed sounds about right.

You are talking about the idle speed adjuster and not the fuel screw, correct? They are two different things.

[trx400EXtreme]

Dont mean to steal your thread Mercedes... but i have a question regarding my idle adjustment screw. when i try to adjust it, nothing happens. i can spin it both ways and nothing changes. it used to work :ermm: . anybody know whats wrong with it?

[GPracer2500]

Originally posted by trx400EXtreme
Dont mean to steal your thread Mercedes... but i have a question regarding my idle adjustment screw. when i try to adjust it, nothing happens. i can spin it both ways and nothing changes. it used to work :ermm: . anybody know whats wrong with it?

That knurled knob is connected to a sheathed cable that is in-turn connected to the screw that actually contacts the carb's throttle valve cam. When you turn that knurled knob you're actually turning a screw on the other side of the carb. The cable can break, making the knurled knob useless. Either replace it or remove the knurled knob completely, yank the cable out of the screw, and turn the base of the screw with needle nose pliers.

Often I'll open the throttle a little when adjusting idles to take pressure off the throttle stop screw. It makes it easier to turn and can save that sheathed cable from wearing out.

[Mercedes]

What is the idle speed adjuster and what is the fuel screw. The one I'm talking about is on the outside of the carb on the same side as the choke lever conected with a black cable.

So just to be sure.... I just adjust it by ear?? Thats it??? Till it sounds right???

So there is no way this will wash my engine??

[GPracer2500]

Originally posted by Mercedes
What is the idle speed adjuster and what is the fuel screw. The one I'm talking about is on the outside of the carb on the same side as the choke lever conected with a black cable.
So just to be sure.... I just adjust it by ear?? Thats it??? Till it sounds right???

So there is no way this will wash my engine??
Yes, that's the idle adjuster.

The fuel screw fine-tunes the jetting of the pilot circuit. It you don't know what/where the fuel screw is, don't worry about it.

There is a idle specification (1400rpm +/-100rpm) but unless you have a tachometer, knowing the spec doesn't help much. So, all you can really do is go by ear. You want it to idle fast enough to be smooth, but not unnecessarily fast.


....So there is no way this will wash my engine??
No way what will wash your engine? I don't understand what your asking.

Is there a specific reason you're so concerned about cylinder wash? That phenomenon is most often associated with idling an engine with an extremely rich mixture (like when the choke is on) for long periods. It has little to nothing to do with idle speed.

[Mercedes]

GPracer2500 thanks for your help.

a friend told me to watch out for the cylinder wash,but i guess that has nothing to do with the adjustment scew.

Now i know,and knowing is half the battle....

I just had to ask....