Kids ATV will not start
 

Bought two Rally 200 4 wheelers for the kids 2005 & 2006.
One needed a transmission gear. The 2006 atv would always start immediatly when the start button was pushed prior to working on transmission. To replace the gear I had to put the ATV on the left side in order to get the gear case back on the gear box. ATV will now not start at all. Has spark at plug, took carb off and looked clean but cleaned it any way, removed plug and it smells like fuel and wet. It acts like it is flooding. It does some small coughing possible backfire, might rarely get a short 1 or 2 second sputter start.
Anyone have any idea where to start?
The timing could not have gotten off by turning it on its side???
Could really use a manual for a 2006 if anyone has one, or its location.

I planned on fixing these prior to telling the kids, but of course they found them and are driving me crazy on when, when, when......:)