Originally Posted by
sweeks
The Shimano TL-CN42 effectively does this with much less fuss. The only problem is that it's a "go/no-go" measuring device.
I have the Shimano tool and it's difficult to know when you're just at the borderline of the pass/fail because just a light push will make it go through. When my chain was at a point where the Shimano tool needed a slightly harder push to get through, my calipers measured around 0.4-0.5% stretch. I had a BBB or X-tools or some other generic tool that measures to the opposite sides of the rollers to include roller wear and it measured 0.75%.