>>>Has anybody ever seen a chain wear indicator tool?
Check out Belgian ebay auction:
http://cgi.benl.ebay.be/
Don't ask me how it is supposed to be used. Steven Maasland<<<
Park has two different chain wear indicator tools, CC-2 and CC-3. CC-3 is relatively new, and is similar to the eBay item. I have a CC-2, which is quite nice.
http://www.parktool.com/
http://www.parktool.com/
Both measure chain "stretch" (distance between a number of links), but chains don't really stretch. As the pieces wear, the links elongate. Chains should regularly be measured for "stretch", because worn chains start to rapidly wear much more expensive parts.
Chains 101.
Wayne Bingham
Falls Church VA