YZ125 What’s this little spring in carb rebuild kit?

[caramall]

2001 YZ 125

 

whats this little spring for I’m rebuild kit?  The idle adjustment screw?  Thanks.
 

 

[DEMI]

Air screw spring or idle, tough to tell from the pic 

Edited August 8, 2020 by DEMI

[caramall]

I took airscrew out and no spring in it.  I don’t think the idle adjust had a spring either (it has a lock nut on the YZ).  

[caramall]

You’re right...air screw.  It was missing.  Not sure why I didn’t see on diagram when I looked ?. Thanks all.

 

 

[MXR]

Looks like the airscrew sprinf

[russell3]

The airscrew should also have a little washer and an o-ring.  I have a 99 yz 125 right now and just did a carb rebuild on it.  Just to clarify, the air screw, spring goes on that, then the little washer, then the o-ring.  hope this helps.  I don't know why it doesn't show those parts in the parts fiche, my kit came with it and I've never seen a carb without the washer and o-ring.

 

Edit:  I could be wrong about the o-ring, maybe it doesn't need that, but it did come in my kit.  It was a Shindy kit I bought from rocky mountain atv.  Now I'm wondering...

Edited August 9, 2020 by russell3

[russell3]

I went out this morning to verify.  I don't think you need the oring and washer, just like it says on the parts diagram.  I took mine out and the washer was kinda bent up, like it shouldn't be there.  I had problems before with it not really adjusting anything when I moved the air screw adjustment and it was running a little rich I think.  I took out the washer and oring and now the screw seats like it should and seemed to have a little adjustment now.  I still have no idea why it came with a washer and oring.  My last few bikes have been older 4 strokes and all had the washer and oring because those carbs have fuel mixture screws instead and operate differently.  I hope this helps and I'm sorry for steering you wrong before!

[caramall]

Thanks for checking!

[russell3]

22 hours ago, caramall said:

Thanks for checking!

No problem, I like stuff like this.  I learn (and in this case, relearn) stuff all the time.