ORIGINAL: Flyer Freq

I just bought my first gas engine. After years of slimers, I decided to try a Brison 3.2. I am at the bottom of the learning curve, and need some reassurance. I have about a gallon of fuel through the engine. I have noticed that there is some slop between the piston and crankshaft. I have assumed that the slop is the play in the needle bearings. It seems more prevalent when warm. The engine runs extremely well, but at idle, I can hear that rattle. Is anything wrong, or am I make a mountain out of nothing? I am running pure synthetic oil, at 80:1, per Brison's manual. 100:1 is my eventual goal, once broken in. Thanks, in advance, for your help!

Andy