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Easy way to determine new chain length?

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Easy way to determine new chain length?

Old 04-14-17, 08:03 PM
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jefnvk
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Easy way to determine new chain length?

I am swapping out my cassette, from a 13-28 to a 14-32. Is there an easy calculation to determine how many links to add compared to the old one sized same as the factory, or is it just better to do the big-big plus 1 rule of thumb for sizing? Not sure if changing the little sprocket too makes any difference on calculating proper chain length.

Front crank chainrings are all the same.
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Old 04-14-17, 08:14 PM
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HerrKaLeun
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sheldon how to calculate chain length

Park Tool video
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Old 04-14-17, 08:34 PM
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Chain wraps 1/2 of each sprocket. So adding 2 teeth to any sprocket, needs 1/2" more chain. Since you can only lengthen in 1" increments, think 1" for every 4t (or fewer).

You may not need to add anything at all. Shift to big/big, and pull the lower loop forward. If you can pull it up 1" or more, you're al set already.
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Old 04-14-17, 09:47 PM
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GCN had an awesome YouTube video on it as well.
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Old 04-14-17, 10:01 PM
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Originally Posted by jefnvk View Post
I am swapping out my cassette, from a 13-28 to a 14-32. Is there an easy calculation to determine how many links to add compared to the old one...
Well, we don't know what the old one was, but if you're looking for calculations, Park Tool has 'em on their page about chain length calculation:

"Simple Equation": L = 2 (C) + (F/4 + R/4 + 1)
L = Chain Length in Inches
C = Chain Stay Length in Inches
F = Number of Teeth on Largest Chainring
R = Number of Teeth on Largest Rear Cog

There's a "rigorous equation", too.
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Old 04-14-17, 10:14 PM
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play it safe, use big to big +1; once you have it set for the larger big cog, it will work fine for the smaller big cog.
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