Originally Posted by
ThermionicScott
It's not a big mystery in this case. With a full-link chain, the pin-to-pin spacing is fixed for each outer link. No matter how much the pins and bushings wear, the two pins for each outer link will never get further apart. So all of the elongation you see is the slop that allows the inner links to migrate outward from each outer link. With a half-link chain, you get that migration in both directions at every single pin, so the elongation adds up twice as fast.
At least, that's my understanding. I'd be surprised if plate deformation played more than an infinitesimal role in all of this.
The thing is that every pin has an inner connection and an outer connection, whether one is using half-links, or normal links.
So, a 100 link chain will have 100 outside connections, and 100 inside connections, no matter whether it is made up of 100 full links, or 100 half links.
I've seen images on the web about chain pins with deep notches. But, I've felt some of my pins that I've removed, and they still seem smooth. Perhaps I'll have to look a bit closer at how the pins fit into the inner links.