That’s what I was afraid of. I’ve had the carbs off, cleaned them thoroughly, replaced the boots and checked all the seals. Spent more time than I care to think about messing with the mixture screws as well. I think I settled on two turns out to get it to where it is now. I think I’m just gonna sell it to someone who has more time and patience than I can spare at this point now that it’s at least halfway rideable. Thanks for all the help though!

 

Unfortunately, hanging rpms is kind of vague. Lot of things can cause that.
I'm guessing that the idle is turned up to about 3k, that why it hangs there.
Then slowly goes lean because of the vacuum leak.
If the idle speed was adjusted correct, then the bike would just stall.

When you cleaned the carbs, did you run a small wire through the all passages and jets.
Add blow out with compressed air.
Some of the small passages are hard to clear if they are really plugged.

 

I sprayed them out with a healthy amount of brake cleaner, ran a wire through them, and blew them out with the air compressor. Also ran brake cleaner through everything again when I had to replace the boots just to verify that everything was still clear. They were in pretty bad shape, the bike had been sitting in some guys shed for quite awhile full of bad gas. The idle being adjusted too high would make a lot of sense though because when I have to choke it to start it for the first time, it revs excessively high, probably around 7000.

 

Sounds like you're doing the right stuff.
Carbs are just hard to diagnose without being there.
You have to go over everything and double check.

7k is way to high at startup.