running rich or lean??

my bike wont run now!
will not getting enought gas make it backfire?

i get a big pop out of the tail pipe and its really hard to kick over! then it pops agian every few kicks
is this a sign of flooding or leaness?

If you can smell gas, it would be running rich. Take a wiff of the exhaust pipe after turning it over a bit. Don't stay there too long though, I'm sure you know what'll happen. Check the plugs, and clean them up if you need to, then turn down the fuel or turn up the air.