I measured a KMC X10 chain and it was 3/32 over (12" ruler method) so I replaced it. Then I punched out a couple of pins and looked the parts over. I noticed the pins came out easier than the pins on sizing a new chain, but looking at the parts it wasn't really obvious what exactly was wearing. I was thinking either the pin to inner side plate, or inner side plate to outer side plate but like I said, neither looked really worn (pin maybe a little rough but not what I would call an indentation). The rollers seem a bit looser, but they don't get involved when measuring the chain length with the ruler method.

scott s.
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