Carb issues 77' cb750k

[ZCook]

Hi all, new to the forum here. I recently purchased a 1977 cb750k with 15k miles. The bike is in awesome condition, my plan is to build a brat/tracker.  I'm having some issues with it running. So far I replaced the points and condensers, plugs, coils, reg. rectifier, battery, rebuilt the carbs completely (I never took them off the rack), k&n pod filters, and it has 4-2-1 pipes. My dad is helping me with the build, he has years of experience with bikes, he raced dirt track professionally for many years where he was his own mechanic, hes now a mechanic for an ama pro team, and now has started a harley shop. That being said we've come to an issue with the bike running, we've yet to sync the carbs but we will be this week. The bike starts up first kick every time, the bike idles extremely low, we give it gas and it cuts out, for whatever reason it won't take fuel. If we pull the choke, and start the bike it idles around 6500-7k, no choke it's around 800, and like I said whenever we give it gas it cuts out. Any help would be awesome! Thanks!

[TOOLS1]

You most likely have a vacuum leak. The rubber boots between the carbs and head are known for this. I would also recommend checking the pilot jets. Unless you removed them and ran a small wire through them they are probably clogged. There is a writeup on here about safely removing them, as they are pressed in. If you do a search, it will come up.
TOOLS

[ZCook]

Awesome! Thanks tools, ill order new boots this week and see if that fixes the problem, and if not ill go back through the carbs and replace the pilot, thats one thing we didn't replace in the carbs.

[TOOLS1]

You do not need to replace them, you just need to clean them.
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[AAchops]

have you tried the idle screw?