How to Replace Mountain Bike Cables
This guide will cover removing the old derailleur cables and installing some new ones on your mountain bike.
- Cable cutters
- Phillips screwdrivers
- 5mm allen wrench
- Needle nose pliers
Most places say to replace cables about twice a year, and housing once a year. That might be necessary if you ride in the mud every day, but for most people, replacing cables once per year and housing every year or two is enough. (I've gone 3-4 years between cable replacements without trouble.)
The key is to watch your cables for signs of wear, such as fraying, and replace them if they look worn. If your cables look and act like new, then there is no need to replace them. However, if they are wearing out, let's replace them...
1. Get new cables. The first thing to do is get a new set of derailleur cables and housing. Make sure to get derailleur cables, which are thinner than brake cables, and derailleur housing, which is made up of many pieces of small-gauge wire that run lengthwise.
2. Check your current set-up. Before you touch your bike, take a look at how the cables are currently routed. For example, how they wrap around the frame and handlebars and where they enter the shifters. You'll want the new cables to be routed the same way.
3. Remove cables. Shift each derailleur to its easiest (smallest) gear. Then take a hex wrench (usually 5 mm) and loosen the pinch bolts on the derailleurs, then slide the cables out. (Cut the cable end caps off if necessary.) Then you can remove all the cables and housing and slide the ends out of the shifters.
4. Prep new cables. Now it's time to cut the new cables and housing. The best way to do that is to line up the old and new cables side-by-side, and cut all the new stuff to match. Make sure to cut the cables and housing using bicycle-specific cable cutters. Then you can crimp ferrules (end caps) onto the cable housing.
5. Install housing. Install the cable housing by placing it in the frame's cable stops.
6. Install cables. Starting at the shifters, install the cable, making sure it is seated in the shifter properly. Then slide the rest through the housing and under the pinch bolt on the derailleur. Pull the cable taut and tighten the pinch bolt. Then crimp on the cable end caps to prevent the cables from fraying.
7. Final adjustments. Now, if the derailleurs still need adjusted properly, you can use the barrel adjusters found on the rear derailleur itself or on the cable stops on the frame. To learn how, see our Front Derailleur Adjustment and Rear Derailleur Adjustment guides.