Reading plugs

1) do not read the plugs only 4 mins in. Your still breaking in, assembly lubes burning off, fuel mixtures still off due to warm up cycle not up to temp, if there is a choke, is it set correctly, etc.
2) focus on the popping. Too lean pop, gasket leak from pop or timing? Valve sticking? Double check spark plug wire order. All bad for any engine let alone new one. Buy an air fuel ratio gauge. That’s the bare minimum you need to make sure all is running properly and the air fuel ratio correct.