Carb Slide Adjustment?

I have VM26s (i think) with the accelerator pump.

What is the adjustment screw in the attached picture for? They don't seem to be all set the same in each of the four carbs.

I know that the needle height is adjusted with the clip. I was wondering if the screw in the picture might be used to affect the moment when the needle starts to rise and unblock the needle jet. I read in my manual that the needle does not start rising out of the needle jet immediately but only after some amount of throttle travel.
I don't think the manual says anything about this.

Thanks

That is to sync the carbs with a set of gauges.
Steve

Ah. Like this guy? Motion Pro 08-0411 Syncpro Carburetor Tuner

YUP Don't try to do it by ear. Bench sync them the fine tune them with the gauges.
Steve

Might not be an issue, as you could be aware of it, but you are missing the lock bolt that holds the lift arm to the common throttle shaft. Is it out on purpose or ???

when your ready to go back together.
I always used a 1mm .039" piece of copper wire. I used the copper "O ring" wire i used for the cylinder block or you can use a paper clip.
You set all 4 slides the same height.
Put the wire at the back side, bottom of the carb body. Put the wire in like a feeler guage under bottom of slide.
Pull it out and adjust the screw up or down to get a slight drag, pulling it out.
Do all 4 slides the same. This way they are all open the same.
Make sure your idle adjuster screw is turn out.
A lot of babble for this!
Just adjust all 4 slides the same with a piece of wire pulling out with a little drag on it.
This is pre-lim.
At least this is what I did years ago with stock carbs. 26mm 76 carbs are the best stock carbs.
Thats why Kaw changed carbs every year from 72-73 - 74 - 75 28 mm's sucked, were cold blooded. That linkage sucked! I used to glue 2 of those stainless shims together to stiffen up the play between the lift parts.
final will be running and with carb syn vacumn guage's, if you have them.
But Good Luck

Thanks everybody!

I bench synced the carbs and adjusted the the floats and she's running a lot better.

I adjusted the slides to have about 1 mm of an opening on the back side and did so with the idle adjustment in the middle of its adjustment range (that seemed to work better than having the idle adjustment all the way out).

-John