Syncronising the carbs on bench

[canwi]

Hi everyone.

Could I get some assistance please on the following:
I am bench synching my 1979 CBX carbs on the bench, making sure all the throttle plates are covering all the three air bleed holes with Idle screw backed right off. Yet I am unable to get the number 4 carb throttle plate to cover all the holes. It covers 2 yet I am concerned that possible the throttle plate may be warped and not allowing to close completely. As this is the base standard carb when performing the Synchronising on all other carbs, is this normal for #4 to still allow 2 air bleed holes to be open?

Thanks for any and all feedback.

[Patriotprop]

The carbs may be miss aligned. I loosened all the braces and relighted one at a time, trying each one and eventually I got everything to line up. The top cross brace was the one that did it for me

[canwi]

Thanks.

Actually I was meaning the tiny little holes located just in front of the throttle plate (on each carb) in the carb body. Seems all the other carbs I can get the holes covered after adjusting the Synch screw and lock nut, but not #4 carb. If this is the factory setting, should I then be adjusting all the other carbs to uncover the 2 tiny holes when fully closed at idle? I.E With 3 holes, should two be left uncovered like they are on #4 carb?

Cheers.

[daves79x]

Try loosening the 2 screws that hold the throttle plate to the shaft just a bit. Then snap the throttle a couple of times to center the plate in the bore, then tighten. Almost every set of carbs has at least one plate that's slightly off and needs re-centered. This is much easier to do when the carbs are still separated as you can tell which ones need this treatment. If each throttle plate is perfectly centered, the throttle will work perfectly smooth and no binding.

That said, are you sure you have your idle adjust screw backed completely off?

You also may have the other carbs misadjusted and they are holding #4 open.

The way you set the sync on the bench is to slightly open the whole bank with the idle adjuster until just the barest amount of the front bleed hole is exposed. This is where you can tell what needs adjusted and when all are perfect at that point, your idle will be pretty close.

Dave

[canwi]

Thanks everyone for your input.

I will go back and recheck the adjustments. Stay tuned:-).