KLF-220 Bayou '99 ( Checking / Setting Timing )

1999 Klf-220 bayou not starting easily and running very rough. Timing was off. Checked for spark and fuel and all was fine. This is just a reference for what I found causing my issues. It seemed like it was an ignition issue since it would idle smooth at 1/4 throttle I figured it had ignition. Any more throttle and it would sputter, and choke off once the throttle was released. As I said in the clip my root cause is a stretched timing chain, and worn tensioner pad. This is letting the chain flop around while its running ( I can hear the rattle). I think but am not positive, that if I cut the engine off using the key instead of the stop switch it will sort of back fire, causing the timing to get off due to the stretched chain. Just a theory though. I hope this helps because I could not find anything, anywhere on the proper way to check the timing on this ATV. This may not be the proper way either but It started first pull after I did it and the atv has more pep than ever now. Who knows how long it was a little off time.