paperassgasket

Hey is there anyone in the NOVA area who might be willing to help me get my bike running?
1977 Honda CB750K (K7)
I've been having trouble with it for a while now. I just can't seem to get it running.
I'm pretty sure it's a carburetor problem but I just can't seem to nail it down.
I've got it to where it will idle around 1500rpm for a minute but it dies.

Info:
The bike came with K&N pod filters and a 4-1 exhaust which I swapped for individual headers to diagnose running problems.

The carbs are the later model Keihin Carbs. They're stamped PD42A (I can't find any info on this specific stamp). They've got 120 Main jets (stock is 115), an adjustable Needle, and stock slow jets. They've been recently rebuilt and cleaned.

I'm fairly sure all the passages and jets are clean since I cleaned the carbs 2x just to be sure. Then sprayed a whole can of carb cleaner through them.

I think the jet needle is set right and I'm going to double check the float height again soon. (maybe tonight?) I'm going to set it to 12mm and see if that helps.

I bench sync'd them but I don't have a vacuum gauge or manometer to sync them on the bike. Although I can't even get the bike to idle properly so that is a moot point.

I believe the carb boots are good as spraying WD-40 on them does not affect idle.

I do not have brand new plugs on there no but all 4 plugs are prob <1 year old and then bike has never run with them on. (I bought someone else's problems)

If there's any additional info you need let me know and I'll get it asap.

paperassgasket

I think I figured it out.
there's brass chunks in the slow jets.
how the fuck they got there...