Sierratim
Well-Known Member
- Region
- USA
- City
- Nevada City, CA & Paradise Valley, AZ
Over the years I've modified gearing on most of my bikes. What to do about the existing chain was always an issue; longer, shorter, who knew until you could wrap it around the biggest cog and front ring. So considering another change I (finally) did the obvious and Googled 'chain length calculator'. Some don't work correctly, some reference the tried and true method I've always done, and others didn't have enough tooth count range in the calculator.
But THIS ONE seems to meet all my needs. For my current setup (48t chain ring, 42t biggest cog, and 478mm chain stay) it correctly calculates the chain at 120 links. For the 46t cog I'm considering it calculates a 122 link chain. For a 50t cog I'd need to go with a 124 link chain, both doable with the replacement 126 link chain I have in the shop. Nice to know.
Unfortunately the 50t cog would require changing the medium cage derailleur to a long cage. More studying...
BTW - My bike is a hard tail. For a FS frame you would need to additional links to these calculated results.
But THIS ONE seems to meet all my needs. For my current setup (48t chain ring, 42t biggest cog, and 478mm chain stay) it correctly calculates the chain at 120 links. For the 46t cog I'm considering it calculates a 122 link chain. For a 50t cog I'd need to go with a 124 link chain, both doable with the replacement 126 link chain I have in the shop. Nice to know.
Unfortunately the 50t cog would require changing the medium cage derailleur to a long cage. More studying...

BTW - My bike is a hard tail. For a FS frame you would need to additional links to these calculated results.
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