Got the oil changed, and took it out to give it the beans.......

[Ranger]

Just curious, what is the condition inside your fuel tank? Your carbs also have small filters in them, is there any dirt inside when you pull them apart? New boots and o rings make a world of difference, the boots especially when pulling you carbs as 30 year old rubber is a PITA.

[Mr. Sinister]

The tank was spotless inside.
I never saw the carbs apart. I took ownership of the bike because the previous owner didn't want to put any more money into it. He said if I paid to get the carbs out of the shop, I could have the bike. I don't think I'll tell him he was having trouble with it because he didn't have an air filter in it........
The front boots are not new, but they checked out. Still plenty flexible, with good o-rings. The rear boots are OK, I just had the lip of one rolled over, so it wasn't sealing.

[Ranger]

You should take the carbs apart yourself and investigate. Just eliminate all causes 1 by 1 especially while its non operational for the time being. Better now than 3 days after riding it to have an issue and start back at the beginning yet again.

[themess]

Well as it turns out, there is NO air filter, just an empty box with what looks like 2 layers of wire mesh towards the front. There is also no lid for the box. Time to start looking for the parts, I guess.
I did find the airbox to carb boot clamps loose enough to spin, so I cinched them down. ....

The PO left your bike in this condition with something as obvious as an air filter, and you trust him to have competenly cleaned and readjusted the carburetors?????

Don't forget valve adjustment.

[Mr. Sinister]

The carbs were cleaned, rebuilt, and synched by a shop. That's how I got the bike. PO didn't want to put the money into it. He said pay to get the carbs out of the shop, and the bike is yours.

[Ranger]

.So did the shop whom worked on the carbs, simply just clean them and put them back together or were they taken in due to a specific problem the PO was having with the bike? Its just odd to work on something without knowing the source of a particular issue, I'm not sure why he didn't have the whole bike checked out. Maybe they pinched a diaphragm which could be affecting its performance as well as the other issues you've noted.

[Mr. Sinister]

The shop did a total rebuild, and the receipt lists the parts.
The bike runs fine now, it was the lack of an air filter. I said this above.
My only remaining question is whether the carbs were actually bad, or of it was simply the lack of an air filter. It doesn't really matter, I know the carbs are good now.