If anyone one could would be awesome. I have a 2006 outlaw 500 irs, it wont start up. Only if is I pulled with my other atv. I thought I had bad rings. I rebuilt the top end. new piston, rings, and new gaskets. I go to start and it sounds like it wants to start but nothing happens. I stick my hand over the exhaust, it back fires on me, and its pushing air out, but its also sucking air in is that normal?