A bike running after shutting it down seems odd and not like a stuck float (although, I would check the floats no matter what, as well as pull all jets and clean them if you haven't).

For the front cylinder not running, check the spark plug, is it wet, dry, fouled, etc.. Is there even a spark?

if the spark plug looks like it did when you put the it in new and it's getting spark, then I would look at fuel, otherwise, check your electrical system.