2007 Rancher 400 won't start
 

My Rancher has about 300 miles and I have not had any problems thus far. I had been on a weekend ride and had 2 days of trouble free riding. Shut it off for the night and when I went to start it in the morning
to load it up to come home, it would not start. I got it home and checked the following:
-changed the plug (lots of spark)
- drained the gas and put new in
- took the carb off and gave it a good clean with carb cleaner
It will fire but won't start. It does seem to back fire through the intake.
Thanks Jim