How to Replace a Shift Cable

Step-by-Step Summary

1. Shift to smallest gear: Release all tension from the shifter by clicking down to the hardest gear (smallest cog).
2. Open shift port: Locate the cable entry port on your shifter (often a plastic dust screw or rubber plug).
3. Remove old cable: Undo the anchor bolt at the derailleur, cut off the old end cap, and push the old cable out through the shifter.
4. Feed new cable: Carefully feed the new cable through the shifter port. Ensure the head seats fully in the ratchet mechanism.
5. Route through housing: Feed cable through your housing. If internal, push the new cable through before pulling the old one if using a liner, otherwise be patient.
6. Anchor and trim: Pull tight at the derailleur, clamp down, and trim the excess.
7. Crimp end cap: Give the cable a tug to "pre-stretch" it, re-tighten anchor bolt, then crimp on an end cap.
8. Adjust Derailleur: You will likely need to re-index your gears after replacing the cable.

[!TIP] Always install a cable end cap. Frayed cables are dangerous and painful!