How many turns on the air/fuel screw

[R1kdxrider]

The one on the carb how mant turns from closed is it? Someone thought it was funny screwing it in all the way.
Thanks

 

[dante]

I've heard 1 1/2 turns is a good place to start

 

[fundgh]

What is the effect of screwing it in or out a little more or a lot more? I was riding yesterday and I was trying to get a slight hickup out of the throttle, and tried the air screw because it was accessable. I didn't really notice a difference between 1 turn out and 2 1/4 turns out. What should I have seen?

 

[John Cena]

http://justkdx.dirtrider.net/carbtuning.html Lots of info here :cool:

 

[jumpingjoe628]

To properly adjust the air screw just warm the bike up to operating temp. and then give the throttle a 1/4 turn and adjust the screw in and out till you find the sweet spot. Screwed in too much will make it rich and the rpms will drop. Screwed out too much will make it too lean and the rpms will rise to a point then it will surging for fuel. Back it off to the sweet spot before the surging. You should do this before each time you ride the bike because the weather conditions are different every day.

 

[Feanor]

1 1/2 turns out is supposed to be the generally accepted starting point...

I've read that you get the bike warmed up completely, then turn the screw all the way in (gently) then back it out 1/4 turn so it will start... start the bike up and adjust the idle speed screw (throttle stop) so that it idles at the lowest speed possible... Then start turning the airscrew out a bit at a time and listen for the idle speed increasing... when the idle speed won't get any faster or smoother by turning the screw out more, that is where you should leave it...

If you find this setting is much more than 2 turns out, then you have to go one step leaner on your pilot jet...

Good luck to you!

Feanor

 

[G. Gearloose]

1 1/2 turns out is supposed to be the generally accepted starting point...

I've read that you get the bike warmed up completely, then turn the screw all the way in (gently) then back it out 1/4 turn so it will start... start the bike up and adjust the idle speed screw (throttle stop) so that it idles at the lowest speed possible... Then start turning the airscrew out a bit at a time and listen for the idle speed increasing... when the idle speed won't get any faster or smoother by turning the screw out more, that is where you should leave it...

If you find this setting is much more than 2 turns out, then you have to go one step leaner on your pilot jet...

Good luck to you!

Feanor

Please pardon my frankness Feanor, but

you described the textbook way to dial in an off-idle hesitation and coarsly choose a pilot jet.

the AS should be set to get the best off-idle snap and stall resistance in gear. Read- setting the As doesn't include running it nuetral. Set to Highest RPMs in neutral equals a lean hesitation off idle.



Also, If anyone is setting the AS to fix 1/4 throttle performance, one has more expansive jetting deficiencies that need correction.

 

[canyncarvr]

re: 'screwing it in all the way'

Don't know about funny...but not helping anything run better.

As GearLoose said...response. Say...2nd gear..under load..slow walk pace...off idle response should be 'crisp'. No hesitation, no bogging, no 'boo-wahhhhh' noise.

There is something that a hi-idle setting of the AS will tell you.

You have it set wrong.

 

[John Harris]

If you are grossly rich on the pilot jet (like it comes from the factory), it usually does not make much difference where you have the air screw set from 1 to three turns out. Any difference in the air screw setting is hard to detect under rich conditions, especially for a novice tuner. Get close on the pilot and have the needle down in the second clip from the top and you will notice how the air screw works! Enjoy the ride John