Chain measurement issues here
In the past I have tried in vain to check my chain wear with wood rulers and metal tape measures but my poor old eyes and crap knees make it difficult for me to get close enough or see well enough to do me much good.
I finally broke down and purchased a chain measurement tool and even got a lesson from the LBS in its proper use. http://www.bikeparts.com/search_resu...p?ID=BPC331423
I also have recently acquired 15" a metal ruler that I can actually see well enough to measure the chain with.
Here's my issue....the tool shows me different results than the ruler does and to varying degrees depending on the bike. On my EZ Sport the tool says the chain is at 100% stretch while the ruler measures the pins at 0% stretch. On my Tour Easy the tool says 60% stretched and the ruler 0% stretch and my Volae the tool says 50% stretched and the ruler 0% stretch.
What am I missing? Are the rollers wearing on these chains showing stretch with the tool yet the holes in the side plates and the pins aren't worn yet giving me passing results with the ruler? Does any of this make sense? I believe that I'm tensioning the chain the same regardless of my measuring method so I'm confused by the variability.