Doesn't start

[ctcfuess]

I have a stock 2002 GS500, that used to stall whenever I came to a stop until it got really warmed up.  I pulled the carbs cleaned them up, and rebuilt them.  When I installed them, it wouldn't start, so I used some starting fluid spraying them into the carbs, and the bike started.  I let it run for a sec, then shut it back down.  Then, I tried again, and it restarted.  I put the air box back on, and couldn't get it to restart.  Then when I pulled the carbs back off, and sprayed more fluid in, nothing happened.  Anyone have any ideas, I checked to make sure I'm getting a spark, and I am getting fuel down to the carbs, so I'm pretty stumped.  Anyone have any ideas?  Thanks.