Quote:

When you talk diameter of the TWO gears you are only
making it about .0005 bigger(and thats on the large
size since you talking PI)... if the rollers have
enough slop between each other then they could make
just the chain shorter... or if they are built to
a CLOSE spec then a shorter chain would have bind
on the rollers to gear... you cant change just one
gear vs the other... givin enough rotations it would
start to change the cam location to the crank



Uh, no!
When they talk "oversize" they actually mean the difference in the line bore from the stock position. So a .005" o/s would be a line bore that id .005" closer to the cam.
The top sprocket ONLY is made oversize. For a .005" o/s, the top sprocket needs to shorten each side of the chain by .005". Since only half the sprocket is in contact with the chain, half the circumference has to take up .010" total. Half the circumference of a 6" diameter sprocket is close to 9.5" so the sprocket has to have about .001" per inch added to its diameter for a total of about .020". No chain will ever notice that.


As to enough rotation changing the position of the crank ... can't happen. The number of teeth is what counts and as long as its the two-to-one ratio, the crank position will never move.