compression test

Check valves, may have needed adjusting? While your in there. @sonny is keeping good notes on his rebuild
 
I've heard them. Exhaust starts making a pinging sound, only heard at idle. Diagnosed one years ago, warned my buddy, they laughed, two weeks latter she sucked one.
But that was on a two valve Harley
 

When cranking I added some WD-40 and it shot up to 210 pretty quick....
 
When cranking I added some WD-40 and it shot up to 210 pretty quick....

It would seem your rings are a bit tired - how many miles has the engine done. You are going to freshen it up in any case aren't you. So it doesn't really matter when you get it apart check things like ring end gap and worn ring grooves and check the condition of the cylinder bores.