Originally Posted by
DaveSSS
Campy chains don't usually elongate very much, unlike other brands. The rollers still wear, however. I use calipers and place the internal tips between the rollers to measure the space between them. When new, the space between them is about .200 inch. I would change a chain when that spacing increase to about .220 inch, but I don't toss my chains. I use three of them in a rotation and try to use them until the spacing is about .235-.240. If you leave a single chain in use for that long, you may get chain skip when a second new chain is installed.
I did this earlier today with my calipers, and measured according to the Campy chain manual (measuring a six-link span). The distance should be no greater than 132.60 mm from the roller of the first to the roller of the last. Mine was 132.22 mm.