How does Sakae Custom determine which bike has the better chainline?
I try to do it by eyeball, but all the frame angles create optical illusions.
As for measuring with calipers, one has to "guess" at the center of the tube.
A better method than eyeballing must exist.

I figure chain noise comes from the teeth and links hitting at a side angle.
It seems to me the better the chainline the quieter the chain; and, conversely, the quieter the chain the better the chainline.