Greetings Everyone

getting back into ATV's and bought a couple used bikes, neither of which ran but i got a good price so decided to pull the trigger. i was able to get one running after boiling out the carb and de-rusting the tank and then coating it with and epoxy fuel tank sealer. This second one i also have running however it has more noise than i expect and kind of sounds like timing chain???? upper end????

The attachment is a wave of the sound of the bike just after starting and of course cold, insight or recommendations are welcome. I have adjusted the valves and found them to be a bit tight so adjusted them to .004 on both intake and exhaust and this has had no effect on the noise but the bike starts right up and will rev but before i go beating on it i want to make sure it is not eating itself up.