Multi-Speed Chain Length

By Brad Quartuccio

Determining chain length on a single speed drivetrain is straightforward enough, but proper chain length on a multi-speed derailleur system isn’t as brainless. Too short of a chain on a multi-speed system can lead to binding and potentially a broken chain or other components—it’s important to have enough chain to wrap around the largest combination of front and rear teeth with space for the rear derailleur. One popular way to determine chain length is to wrap the chain around the large chainring and largest cog, without going through the rear derailleur, and pull it tight. Note the shortest length it could be joined and add two links (one inch) of chain to account for the rear derailleur. If you are using a master link be sure to account for its length in your link addition.