How to Replace an Inner Shift Cable
Remove the old inner shift wire and install a new one.
- How to Replace Cable Housings
- How to Adjust Your Rear Derailleur
- How to Adjust Your Front Derailleur
Shift cable inner wires wear out over time. Other than obvious fraying, rust or visual wear, you can tell your cables are worn when your shifting starts to feel sluggish. If lubricating the housings or shift levers doesn’t help, they’ll likely need replacing.
For this job, you’ll need a replacement shift cable inner wire. Shift cable ends have a cylinder barrel shape as shown here. I recommend stainless steel cables if you’re riding regularly in a wet climate, as they won’t rust. You’ll need a good set of wire cutters, some bicycle specific cable cutters if you’ll be replacing the outer cable housing, and some triflow or light lubricant. You’ll need either a 9 or 10mm metric open end wrench or a 5 or 6mm hex key for the derailleur’s cable pinch bolt. You’ll also need to know how to adjust your front or rear derailleur, as explained in previous tutorials.
Shift Cable Removal
The first step is to relieve cable tension by shifting your derailleur so the chain is on the smallest sprocket on either your front or rear derailleur.
Carefully observe how your cable is presently routed from the shift lever to your derailleur. A misrouted cable can cause many problems. It may help to photograph each section of the cable from the shifter to the derailleur so you can use it for reference. Your derailleur may not look exactly like the one pictured here, but the concepts will be the same.
Now disconnect the cable at the derailleur’s pinch bolt. Notice how the cable is flattened where it was pinched. I like to cut the cable just before this part so it is easier to remove by sliding through the outer cable housings. I recommend replacing the outer cable housings at the same time. See the tutorial titled “How to Replace Cable Housings”.
Shift Cable Installation
Once you have nothing but the shift lever and the cable left, push the cable gently until you see the head poke out of the lever. Now you can pull it the rest of the way until it is completely removed. Depending on what type of shifters you have, reinserting the new cable can be tricky. I like to give the end of the cable a slight bend to help guide it through. If it meets resistance, try rotating the cable a little bit and gently pushing until it slides all the way through.
If your shifter has a barrel adjuster, turn it clockwise all the way and then back it off one full turn. Drop some light oil into your cable housings and make sure the outer housing’s cable ferrules are firmly in place before carefully sliding the new cable through the housing. If your derailleur has a barrel adjuster, tighten it all the way clockwise and then back it off one full turn. Then route your cable the same way it was before and thread the inner cable under the derailleur’s pinch bolt washer. Often there is a groove on the derailleur where the cable is meant to sit. Pull the cable tight and tighten the pinch bolt. The cable will flatten when tightened. Always tighten bolts to the manufacturer’s torque specifications. Adjust the derailleur as needed. See the related tutorials for tips on adjusting derailleurs.
Once installed and adjusted, cut the wire about 2 inches further along the cable. Your new cable should have come with a cable end that can be gently crimped on using wire cutters or pliers. This will prevent fraying.
- Shimano TL-CT10 Cable Cutter
- Park Tool HXS-1.2 Hex Wrench Set
- Park Tool Wrench Combo Set
- Hozan 4th Hand Cable Puller
- Park Tool SK-3 Starter Mechanic Tool Kit
- Park Tool PK-3 Professional Tool Kit
Discuss this topic in the Cable Forums
Hi - I am working on a wheelchair rather than a bicycle however it does have caliper brakes on both back wheels which are controlled by regular brake levers located on the wheelchair hand grasps (at the back). I want to control the brake levers remotely via two servo motors. I need to move the location of the brake levers so that someone can still push the wheel chair and that the servo motors won...Read more
Welcome back! About 2 months ago, I put new cables on both the bikes (1970 Gitane, 1980 Peugeot) I've been restoring... I have been checking the alignment of the gearing and brakes, and I believe I've noticed a minor 'new cable stretch' for lack of a better term.... What I'm trying to say is, I'm noticing a slight re-adjustment in brakes and derailleur adjustment that's needed a couple months ...Read more
I am getting a 1978 Raleigh Grand Prix road bike into riding condition. The derailleur cables need replacing. Can I use standard cables found at a local bike shop or do I need to find special "vintage" cables online? This is my first bike repair project, so any help would be appreciated. ---Anders...Read more
Just about to replace the inner cable on my XT M8000 11 speed shifter. Can anyone tell me if I need to use the Optislick inner cable or would a PTFE one be fine. Also does the Optislick cable have a different housing. Cheers Stevo...Read more
Hello Can anyone tell me the difference between galvanised and stainless steel cables/wires? From what I have read online, stainless steel doesn't rust. I have bought some cables, so how do I check what material it is? Thank you...Read more
Hi guys I know the difference between the 2 cables but how do I spot the difference between the 2? I have bought both cables and they will be delivered later this week. Is there a difference visually, feel wise? Thanks...Read more
Hello Can anyone tell me what PE lined brake cable mean? Also how do i tell if the cable is PE lined or not when looking at it? I have had a quick look on google and no luck so far. Thanks...Read more
Hi guys, So I've recently noticed that my rear dérailleur has almost completely lost its ability to shift the chain between sprockets (on a good day, it can move between two of the seven rear sprockets). I think I've found the source of the problem in the shift mechanism: [attachment=5372] In the photo, you can see the dérailleur cable enter a white plastic part (just below the "2"). You can...Read more
I was having issues with my bike chain slipping on the front derailleur mid ride and skipping gears on the rear when shifting. Did some reading determined that my derailleurs probably needed adjusting, most likely because as a relatively new bike the cables would have stretched. I had my housemate have a look (he has a little bit of bike knowledge) he twisted the H and L screws and the barrel adju...Read more
Can anyone tell me where to begin when resetting the position of the front derailer and shift cables on a cheep older Walmart bike? I was trying to fix the scrapping of the derailer and shifting problems but messed up and loosened the shift cable bolt and can't get anything back. I loose the large ring or the small during shifting so I need to start from scratch...but where?...Read more
Hi! Newcomer here. I am the proud owner of a KTM Ultra Fun So far it has been nothing but joy, until recently the right-hand gear-shift cable decided to burst and detach from the gear-shift lever (Shimano ST M410) in the middle of a ride, part of the cable remaining inside... The first pic below shows the large fraction of cable as I was able to retrieve. The second one zooms into the broken en...Read more
I recently got a Trek Antelope 800, and the thumb shifter is broken. I have found a thumb shifter (Shimano Tourney SL-TX50) but I am not sure if it comes with the cables I need to install. Anyone know where I could get these cables?...Read more
I'm putting my plan together to fix up a Fuji Allegro, and I'm curious if I can tuck the cable housing for the brakes under the handlebar tape, or if it must be above. Not a deal breaker either way, just curious if it is a functional idea....Read more
[attachment=4841]I have a non-branded carbon fiber TT bike (Cervelo P3) purchased on the internet. It looks very similar to the picture posted. The problem is once the shift cables are installed and adjusted the shifting only works a couple of times or less and then hangs up and the cable binds up somehow and the bike will not change gears. When you take the tension off, the cable will slide ba...Read more
So I bought a new Schwinn bike to replace my old one that got stolen, and on the first set of gears (the ones connected to the pedals) the cable wasn't taught enough to switch gears. So, I researched, and found that the cable had to be tighter. So I thightened it. Now it goes up to 3 from the first gear, but it won't go down to the 2nd gear. So I turned the dial to one, and it went to one. It won'...Read more