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Did I screw up the install of my new chain.....(3 posts)

Did I screw up the install of my new chain.....bent_spoke
Jun 25, 2003 7:23 PM
I just added a new cassette & was replacing the chain as well. I cut the chain with 2 links to spare as recommended, althought it seemed more like 2 1/2 links. I ended up with 2 similar ends to the chain so I had to take another link out. Does anyone know how I can tell if this will be ok or should I just add something back??
re: Did I screw up the install of my new chain.....M_Currie
Jun 25, 2003 7:53 PM
As a general rough rule: if the chain still has some tension when it's in the smallest/smallest combination, it isn't too long. If there's still some spring left in the derailleur when it's in the largest/largest combination, it isn't too short.
Jun 26, 2003 4:32 AM
From down the page, June 19:

In case you're not familiar with adjusting chain length, there's more than one method, but this method insures that the chain is the set to the maximum useable length, to provide the greatest capacity.

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. 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. It won't help keep the chain from skipping or jumping.

Second, the chain must be long enough to avoid overextending 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 capacity.

If you want to see how much lower pulley movement will occur, without removing the extra two links, shift up four teeth (11 to 15 or 12 to 16). This has the same effect as removing two links.

SRAM chains still have protruding pins that can be removed and replaced without too much chance of failure. Most other chains either cannot have links added back in (campy 10 and wipperman) or require a new pin (shimano). Chains come with instructions. Never hurts to read them.