So discovery is always interesting -I had little ping marks on the top of the top of the piston and on the head.  I think I know why - the tip of the ring was missing.  I ordered new rings but did not notice I had a wiseco piston and of course the yamaha ring are not correct.  I got a set of wiseco .50 rings that are correct but notice the ring gap is too tight.  That  might be why the old ring broke in the first place.  Anyway using the bore x ,004 I get a measurement that is too tight so I am heading the to the machine shop to grind back a little - SO MY QUESTION IS? - IS THE TOP RING THE SAME AS THE BOTTOM RING GAP?  I KNOW FOR SOME THEY DIFFER, BUT FOR A WISECO PISTON AND RING ARE THEY THE SAME.  as always thinks guys for all your help 

I probably had the same 0.5mm over wiseco piston in my 175. Does it have "CD" stamped on top? IE, "CD" rings. Mine were gapped ~0.012". Both of my rings, same gap. The engine had run for decades like this.

I question your bore/piston, setup though. usually the rings are good to go as packaged.

Thank you for the response. The bike was run many years after the overbore. I received it from a friend after many years stored in the garage. I was close on the gap - My esto,ates had it at .0104 and that would not fit in the gap. I will grind back just a slight bit to make it meet the .004 x bore standard and ,005 x bore for the second ring per wiseco.