Well, I had reinstalled my newly re-jetted carbs and installed a fuel filter. Once I put the carbs back on and a fuel filter on, the bike wouldn't start.....see this thread:

http://gstwins.com/forum/viewtopic.php?t=16731&highlight=

Well, I replaced the fuel hoses because I didn't care for the condition that the old ones were in and once I put the bike back together, it wouldn't start again. However, I fiddled with the hoses a bit and set the fuel lever to PRI for a couple minutes. Once I did that I tried to start the bike again and HOLY CRAP, it actually started. I let the bike run with the choke on for a couple minutes, then put it to about a quarter choke and everything was fine. Well, after a few minutes of letting it sit and run and revving it lightly from time to time, the bike died. I started it up again and just let it idle completely without giving it throttle, but it died again after a couple minutes. I noticed that my fuel hose going from my petcock to my carbs was a little pinched, so I straightened it out and set the lever to PRI again for a short bit. I started it again and it seemed to be doing okay. I rode it for a bit and it seemed to be riding very jumpy and not really that great, but once I shifted a couple times it seemed to be doing fine. I rode for maybe 4 minutes, then turned the bike off and stored it back in the garage. Came out later that night to try and run it again. It started up but died soon after. Once it died I set the lever to PRI again, hoping that maybe the carbs needed to get fuel or something again, but I had no luck starting it, it just reverted to doing the same thing it was in my previous thread with cranking but not starting.

GOD BLESS anyone that took the time to read that and is willing to give me a suggestion on where to go from here. Thanks guys!

Could it be possible that you've mis-plumbed the hoses? Here is a diagram of the hoses courtesy of Mr. Kerry's website.

This sounds like fuel starvation for one reason or another.

the flow valve under the tank is barely cracked open

Flow valve under the tank? Please elaborate.....

what year is your bike??

1997

you know how to take the tank off?

Yes, I've taken it off numerous times already. I've even unscrewed the petcock from the tank before (don't ask why).

There is a screwdriver operated petcock under side of tank, that's gotta be vertical to be open fully.  That's davipu's suggestion.
Now I have a better theory ... I have seen it in action too ... The screwdriver slot is supposed to be accessed from the right side of bike ... people fit it on left ... that's OK but they'd ahve to correspondingly swap the inside pick up/filter around to compensate ... They dont ... so when you ahve it in ON its reserve and res is on and worse ... prime connects reserve to carbs wihtout vacuum, and you now have on to res wihtout vacuum ... so not enough fuel in tank and the bike wont respond on prime or reserve ... So you're probably going to have to try it in on as its running if that's the case.
Cool.
Srinath.

damn Srinath, you just had to ruin my fun didn't you?  you know I was getting ready to tell him that it was cause his rear tire was low and it was throwing off his carb floats.   but no you just had to ruin it.....

srinath.....thanks for the analysis, but what should I do with that knowledge? Is the little screw that needs to be vertical sticking out on the side of the fuel-mounted petcock? Am I picturing the right part?

So I should just take off the tank and turn that screw vertical? When I took the petcock off, I remembered to install it exactly as it was before, so that I'm sure I didn't change anything on the bike from what it was like before.

yeah, just turn it to vertical

Well I believe there is plenty scope for screw up's without our help  :lol:  ... If I posted 1/10th the crap I see in peoples bikes You'd all call me insane ...  I am currently working on a bike that seems to snap off every 5th bolt ... man like what's wiht this thing ...
Cool.
Srinath.

I don't understand why it would not be in a vertical position already....the p.o. supposedly was running the bike perfectly before he sold it to me, and it wouldn't have run smoothly if the screw wasn't vertical. Does the screw sometimes just work itself out of place?

Oh, thanks again for the jets, srinath! Got em installed in a snap....I'm just waiting on the bike to run like a champ to send you the DJ mains and needles.

nope, but as you siad yourself you removed the tank several times, when you pull the hoses off if you need to close that pet chicken so that the fuel dosn't run on the ground.  and when you put the tank back on, you need to open it back up.

Well.....I'm an idiot and I didn't realize there was a screw to close it off. I just emptied the tank every time I removed it so fuel wouldn't pour out. I never turned the screw.

Perhaps that's not the problem, then....

then maybe a pinched hose, or a bad line/ connection on the vaccum line that connects from the petcock to the carbs

OK then you have the screw facing left of bike or right ...
Cool.
Srinath.

Screw facing right.