Originally Posted by peripatetic
My question, put another way: will there be a significant variation in number of links and/or in the length of each link itself between an old chain and a new chain? It's the first time I'm replacing a new chain, and I don't want to try and put it on the bike and have the shifting not work and THEN try and take the thing back to the bike shop to replace. From the ambiguity of the two responses so far, I'm going to assume that I'm just going to have to figure this out myself. Thanks anyway.
You can't see stretch or wear in one link,bu eyeball...
New chains are typically too long and have to be sized to length. New Sram chains had 114 links,and older ons had 116. The OP had it right when he said to count the links in both, and the answer will be obvious.I don't think you are gong to get 4" of elongation in a chain length as 1/8" per foort is wore out and 1/4" pre foot probably wouldn't even work.You have less than 5' of total new chain to work with,so how much stretch could you realistically have? ...
www.parktool.com repair section has the drill on chain sizing.