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Switching to a 29 tooth campy rear cassette and just wondering how many links you guys are using for the Campy crankset/29 tooth rear sprocket combination. I am used to a 26 tooth setup which I was using 108 total links out of the 114. I know the basic setup of chain length and will adjust accordingly, but just thought I'd see what you guys are using. And yes, I am using a medium cage rear derailleur. (Just in case you were wondering).

Thanks in advance
 

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Bloatedpig said:
Switching to a 29 tooth campy rear cassette and just wondering how many links you guys are using for the Campy crankset/29 tooth rear sprocket combination. I am used to a 26 tooth setup which I was using 108 total links out of the 114. I know the basic setup of chain length and will adjust accordingly, but just thought I'd see what you guys are using. And yes, I am using a medium cage rear derailleur. (Just in case you were wondering).

Thanks in advance

You can go here and read all about a few different ways of determining chain length. RBR search will help, too.
 

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You an also use this formula:
L = 2(C) + F/4 + R/4 + [(F-R)squared x .01275 x (1/C)] + 1
L = Chain Length
F = No. of teeth on Large Chainring
R = No. or teeth on large cog (in your case, the 29)
C = Chainstay length in inches, rounded to closet 1/8" and converted to decimal.
 

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irrelevant...

How many links somebody else uses is totally irrelevant. You use the amount you need, depending on your chainstay length.

If you set the bike up properly with a 26, then you need 1 inch more for a 29, since every tooth equals 1/4 inch and you can only make 1 inch minimum changes.

Here's the right way to adjust chain length.

Two simple tests will determine if the chain is the correct length. First, it must not hang loose in the little ring, little cog combination. If there is no tension on the chain in the little ring, little cog combination; remove two links (one inch) at a time, until there is. When the ends of the chain are brought together, some movement of the lower pulley should occur, indicating tension is being applied. Two more links (another inch) may need to be removed, beyond the point of absolute minimum tension, to keep the chain from rubbing on itself or the chain guide tab as it passes under the upper derailleur pulley. If you want to see how much lower pulley movement will occur, without removing the extra inch of chain, shift up four teeth (11 to 15 or 12 to 16). This has the same effect as removing two links. Once this is done, the chain is set to the maximum useable length. Removing additional links will do nothing but reduce the derailleur's capacity.

Second, the chain must be long enough to avoid over-extending the rear derailleur when shifted to the big ring and biggest cog combination. If the chain is set to the maximum length as described, it should always pass this test, unless your setup exceeds the derailleur's stated wrap capacity. If you deliberately exceed the derailleur's capacity and the derailleur is over-extended in the big ring/largest cog combo, then you must either avoid that combo or add another inch and avoid using the little chainring and the smallest 3 or 4 cogs (since the chain will hang loose).
 
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