I tried starting her up for the first time this year and can't get her done.  First the battery was dead so I replaced it.  I also drained the old gas out and filled the tank.  Now she will turn over but only run for a few seconds.  I thought that maybe she wasn't getting fuel.  I pulled the large house that connects the petcock to the bowl.  With the petcock switched to On or Reserve there is no fuel coming out of this hose but if I switch it to Prime, fuel flows out the hose.  Is this normal?  I also noticed that if I left it in the Prime position, fuel flows out of the tube that points straight down underneath the bike.  Is this normal?  Any suggestions on what could be going on?  Thanks in advance for your help.

So the tube on the very bottom of the bike is fuel overflow? Somehow I thought that was related to oil.  Could it be a spark plug issue?

And in other words, your bike won't start........or run right because it is majorly flooding.

If rapping the carb w/ a plastic handle screw driver doesn't stop the flooding, maybe try turning the petcock back to on, which will stop the gas flow, then loosen the drain screw on the bottom of the carb bowl and drain it. This will let the float drop, which opens the valve that is leaking. Close the drain, and turn the Petcock back to prime.
Hopefully, the inrush of fuel will wash the valve free of any foreign material that was causing it to leak. In a few seconds, the bowl should fill and the float valve should shut the fuel completely off.
And if by chance this fixes the problem, give your bike a break by installing a very small fuel filter tween the petcock and the carb.

Mine hasnt been started in over 2 years. I drained the bowl, got just about a teaspoon of green stuff,, foul smelling,

I tried the suggestion of draining the bowl and setting it to prime. Still no dice.  I also removed the hose going to the airbox.  The float that sits inside the carb was in the down position.  I wiggled it up and down to see if it moves freely. No problems there.  Im going to put a new spark plug in.  If it doesn't work after that, I don't know what to do.

on the use of seafoam an ounce or two in the tank will help keep the carb clean.  In severe cases, fill the bowl and let sit overnight.  drain it and pour it in the tank cause it won't run on seafoam.

being that you cleaned the carb, we're only trying to clean something you missed.

how's the drain tube now?

How's your air filter?
a dirty filter will cause it to run rich and it has kept a savage from running before.

are you doing anything different from the last time it ran?

Well, I thought I had everything worked out yesterday.  I checked the air filter and it was ok so I decided to remove the carb and clean it up.  Once I got everything back together she fired right up.  I gave her several minutes to warm up until she would eventually idle with the choke in.  I took her for a test ride and all was not well.  From the start she had a nice burst of power that lasted maybe 2 seconds but then she would bog down, backfire, and almost die.  I tried pulling the choke back out to half and adjust the idle screw but niether really had an effect.  Any ideas at this point?

I installed a brand new spark plug.  I did try setting it to prime and blocking off the vaccum hose and nipple like others have suggested.  This actually seemed to make it run worse.  When I took the carb apart, everything seemed pretty clean. Not sure exactly what you mean by "carb boot".