Over the past few months, I have been renovating my carbs and linkage. All carb and link parts are new. Now that everything is installed, the throttle lever is loose on the throttle shaft (this was also the way it was prior to the renovation- this is part of the reason for the renovation). This is obviously not good for calibration and such. If I tighten the nut that holds the throttle lever to the throttle shaft more, the throttle shaft doesn't rotate.

I realize there is probably an easy answer. Please let me know what I am missing.

Thank you

There is a nut on the end. Is that loose?

It is somewhat tightened however if I tighten it to much then the throttle shaft doesn't rotate.

You might be missing a washer that goes between the body and the arm.

I know what you are going through, if you are talking about rotational play. I had the same problem with some 44's. What happened in my case was I could not get my new throttle shaft arms to fit onto the throttle shafts because the knockouts are stamped and inaccurate. I took a little file and had to hog them out a bit to make them fit onto the shafts. I took a little too much off one of the arms which allowed it to have a bit of rotational play on the shaft (which makes them un-synchable). To resolve the problem, I removed the loose one and peened it a bit around the knockout to tighten it back up. Hope this helps.
It would be helpful to know the proper method of getting those tight little arms on the shafts without damaging the shafts, I tried heating them but it didn't work. If anyone knows, please chime in.

Precisely what I am going through. I will give it a shot tonight. Thanks.