A little help please

[600dollar650]

Hey guys I need some help. I changed the oil, filter, and plugs on my bike yesterday. Man were they old!!!! I also put on some custom rear blinkers, the stock ones stuck out to far for my taste. But the problem is, after I put everything back together, I can't get the bike to start. First I thought it was the plugs, so I checked them, and they were firing right. I took the tank off, and noticed that when I turned to petcock on, no gas flowed out. Is this my problem, or does anybody have an idea what it could be? Thanks.

[Bumblebee]

1. Verify the correct plug wires go to the correct plugs. If they're reversed, they're 180 degrees out of phase with compression.
2. Verify the vacuum hose from the carburetor to the vacuum shutoff valve is attached. I think the vacuum shutoff is on the petcock for the 83+ models which means there is a fuel line and a vacuum line attached to the petcock. If that vacuum hose is removed, no fuel will come out of the tank.