Got a carb syncing tool. This is what it told me.

[ZombiePotatoSalad]

Here's the results: https://vimeo.com/417850311

[Big T]

Did you calibrate all of the gauges prior to starting the sync?

Those readings are not close enough, so adjust away

[ZombiePotatoSalad]

I adjusted it, and it didn't wiggle far.

[chuck hahn]

What did you adjust? Those gauges usually have a small brass screw you can manually move the needles with to get them all at the same reading BEFORE hooking them to the bike. Secondly, you need to dampen the lines better so the needles dont wobble around. Sync at around 2,000 RPM and blip the throttle 2 or 3 times then recheck the needles..readust if need be. Then run it up to about 4,000 and hold it for a few seconds and see where they are at "riding" RPMs.

[Steve]

The engine speed is too high.

The vacuum levels are not synchronized.

Not sure why it died at the end.

Lastly, Carbtune might sue you for using their name on that gauge set. That is NOT a Carbtune.

.

[chuck hahn]

In your video just before you cranked it i froze the video. i can clearly see that only one needle is on zero. unscrew the lenses and turn that little screw with the slot and get all 4 needles setting exactly on zero and try again.
And they look a lot like the blue Emgo gauges

[ZombiePotatoSalad]

In your video just before you cranked it i froze the video. i can clearly see that only one needle is on zero. unscrew the lenses and turn that little screw with the slot and get all 4 needles setting exactly on zero and try again.
And they look a lot like the blue Emgo gauges

Which one? 1, 2, 3, or 4? I hooked it up and turned on the engine, none of the needles moved. So I then adjusted each knob until the needles moved, then tightened the knobs so the needles weren't all over the place. They each settled in the red zone. And yeah, I believe they are, some offshoot or something.

@Steve I know, that's just the word that came to mind. I'm not branding it, that's just what I called it at the time of typing. I'm from Texas, where every soda is Coke, every printer paper is Xerox, and every facial tissue is Kleenex.
It died because I pushed the choke in.
I set the idle screw to just touching the mixture screw hole, which I heard is a good baseline idle.
When I originally started it, it only ran around 1,000 RPM with choke fully out. After a while, it caught up. It does then when I take the gas tank off and the carbs are empty. Trying the method you told me about by turning the petcock didn't do anything this time, so I had to spray fuel through the airbox.

[ZombiePotatoSalad]

What did you adjust? Those gauges usually have a small brass screw you can manually move the needles with to get them all at the same reading BEFORE hooking them to the bike. Secondly, you need to dampen the lines better so the needles dont wobble around. Sync at around 2,000 RPM and blip the throttle 2 or 3 times then recheck the needles..readust if need be. Then run it up to about 4,000 and hold it for a few seconds and see where they are at "riding" RPMs.

How would I know they're at the same setting if I have no visual indication while they're off the bike?
All I've been able to see are videos online, I've never done something like this before...

[ZombiePotatoSalad]

As for the rattling sound you hear, that's one of the metal covers that goes over the exhaust pipes, near where they branch underneath. I lost the screw that went in there, so that knocks around when it revs above 3,000. I need to get a replacement screw for that.

If anyone has Discord and would be willing to video call me and walk me through it, that would help.

[chuck hahn]

Did you read all my post? the faces should unscrew and you MANUALLY set all 4 needles to be exactly on the zero point before even hooking them to the bike. And yes once you start the bike you use the dampener things to get the needles steady..then you proceed with syncing.

[ZombiePotatoSalad]

Did you read all my post? the faces should unscrew and you MANUALLY set all 4 needles to be exactly on the zero point before even hooking them to the bike. And yes once you start the bike you use the dampener things to get the needles steady..then you proceed with syncing.

I've tried that. It's hard for me to feel exactly when they set and start to tighten. I can't find the zone between "off" and "loose seat."
Also, one of the channels has a section broken off, so one of the mixture screws nearly falls out when it is loose enough.

[Big T]

Actually, I believe you need to adjust the dials as d scribed, then hook them up one at a time to a single cylinder to calibrate them to one another.

[Big T]

Plus, you have to have your bike actually running to sync.

Starting fluid and choke? You need more carb cleaning

[ZombiePotatoSalad]

Actually, I believe you need to adjust the dials as d scribed, then hook them up one at a time to a single cylinder to calibrate them to one another.

Which is the main carb that all the others are based off of? #3?

[ZombiePotatoSalad]

Plus, you have to have your bike actually running to sync.

Starting fluid and choke? You need more carb cleaning

I took it apart and sprayed carb cleaner into all the holes and blew them out with compressed air. It couldn't get any cleaner.
Even after I had it professionally cleaned, it still ran rough. That's why I'm thinking it's the valves. I'm also going to try to find a better cap for the vacuum port, and see if that helps. I'll try it again tomorrow, weather permitting.