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sure...

I assume that you are using the SRAM connector link to rejoin the chain.

Here's the best way to be sure your chain is the right 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 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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Discussion Starter · #3 ·
Thanks

Yes I am going to connect with the connector. I was going on the basis that my old chain was the right length so the new one should be the same, but thanks for the info on proper sizing.

I just wanted to be sure that I could remove links with a normal chain tool (I have never used a hollow pin chain before).
 

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A wheelist
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You've got it all back-arsewards. The most important thing is that there is enough chain for the big-big combo. Failure to do this will result in equipment damage if that combo is mistakenly used.

This is easy to figure - SRAM says this ~ run the chain around the big-big without going through the derailer, match up the ends and add two links (1").

The downside to this is that you may get some chain droop in the small/small combo - much better than a bent derailer.

I'd rather avoid the small/small combo than the big/big anyday. How many of us haven't shifted into big/big by mistake in the heat of the moment?
 

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Mike T. said:
You've got it all back-arsewards. The most important thing is that there is enough chain for the big-big combo. Failure to do this will result in equipment damage if that combo is mistakenly used.

This is easy to figure - SRAM says this ~ run the chain around the big-big without going through the derailer, match up the ends and add two links (1").

The downside to this is that you may get some chain droop in the small/small combo - much better than a bent derailer.

I'd rather avoid the small/small combo than the big/big anyday. How many of us haven't shifted into big/big by mistake in the heat of the moment?
Yeah, I always go with the big/ big, and let the small/small fall where it will. Never has a problem.
 

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can't read???

My instructions cover both the small/small and big/big situation:

“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.”

Unless you are deliberately using a large cog that is too large for the derailleur or deliberately exceeding the stated capacity of the derailleur, the instructions are accurate. I also include how to handle an over capacity situation.

If you happen to be using an 11-21 cassette and set the chain length by the big/big combo and later decide to switch to a 12-27 for a hilly ride, you WILL have a problem.

Using my method insures that the chain is set to the maximum length that will provide the derailleur's full capacity.

If you try a setup that exceeds the derailleurs capacity, it SHOULD pass the big/big test but it does not have to. There are folks who want the use of the smaller cogs with the middle ring of a double or the little ring of a triple and adjust the chain length only long enough for the big ring and the next to largest cog. This could get you in trouble, but some folks are willing to take the risk. Personally, I buy the right parts that will work together, so I don't deal with these issues.
 

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Cory said:
It's really dumb that you can't (nm) in the new format.
Not that C-40 is wrong. What he says is right if your are switching cassettes and and using out of spec derailers. I have just never been a casette switcher, and if I were to do it, I would always check the big/big 'just in case'.
 
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