So she starts up fine, runs well 20 miles, 100 miles etc, until I turn her off and then start up again. A clacking type sound shows up, fairly loud from the top of engine I believe. It increases in repetition when I rev up, and slows down when throttle is idling. Basically a clackclackclack to clack...clack..clack.

Engine is running a little hot, but nothing too far past half on the temp gauge.

Friend tells me is a rod arm that needs adjusting. Dies this sound right? Anyone else have this issue? Tried a search but not quite sure what I'm dealing with.

No loss in power and overall running very well.