I have already replaced a lot of bolts on the bike with stainless steel ones : it seems that wherever you put a hex driver or wrench, the paint comes off and it starts to rust after a shower or two, and there has been a lot of rain around here lately.
Ferrules are those little bits at the ends of the cable tubes. Those on my E-bike were chromed metal and they were rusting within a week of rain hitting them.
“No problem” I thought, and bought a set of replacement corrosion proof ferrules, cables and the tool to cut the tubing.
A little detail on the nature of bike cables: the brake cables and shifter cables are not the same. Yes, they look the same but they are not. The brake cables are thicker and have 5 mm tubes. These tubes have a spiral wound metal tube with plastic covering outside and slick plastic liner inside. The shifter cables run in 4 mm tubes and the metal tube is more like a hollow cable itself: the strands run along the tube which makes a stiffer tube, more resistant to tension. You should not mix them up. The top ends of them have fittings specific to their function and this should help you figure out what they are if you don’t know.
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| Left - Brake cable, Right - Shifter cable |
I started out replacing the tubes on the brake cables. The tube cutter worked fine, Then I filed the cut ends to get them neat and used the pointed bit on the tool to make sure the hole in the middle was clear to run the cable through. In a short time the replacements were done. I did not fix the new alloy ferrules to the cable tubes but it does not matter as they aren’t going anywhere. I also lubed the cables with dry lube.
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| Cable tube tool |
The shifter cable was a whole different thing. First, the shifter cable has three tubes on it. I didn’t know about the difference between tubes at that point and went to chop it with the same tool I used for the brake cables – it just made a mess. It distorted the tube and didn’t cut all of the strands. Fortunately I have a "grinder" tool and so I used that to cut the end of the tube off neatly. It took me a couple of tries to work this out as the heat from cutting melted the plastic on my first try – if you want to cut the tubing this way, chop a little at a time and wait for it to cool off before cutting more. This gives a very neat end provided that you are patient. Then you only need something like a piece of wire or a bent paperclip to clear the end of the hole and it is ready to use.
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| The "grinder" tool with saw blade |
This would have made fitting the cable tubes easy and fine except that . . . The cable itself decided to lose a fibre. This rucked up when I put a tube on and made using the tubes impossible. Once it is bent you can’t really unbend it. A frayed thread or fibre can be rewound back into the cable if it is still curled as it was before but a sharp bend in one is another story. All I could do was cut it off high enough that the cut tip did not scrape on the tubes and wind it carefully back into the bundle.
I now have a new shifter cable and will try to fit this soon. Fortunately, the end of the new cable is already fused together. Fine until you have fitted it and then you will probably want to trim off the end so it doesn't hang down – and there, your fused end is gone. Also, once you undo the cable from its clamp at the end it is squashed and this can make it hard to pull the tubes off or get new ones on. Oh, yes – there is more than one end design, depending on the maker of the equipment.
I would have already put a new cable on except that I don't know how to get the top end out of the controller.
I have opened the side of the shifter controller but I can’t see either the end of the cable or where to remove it.
I went to the maker's website and got the service info for the specific model and . . . . it says nothing about how to replace the cable. Nothing. Cable part number, picture of it, yes - how to do it, no. The trouble with flying blind is that if anything goes wrong, for example a spring flying out of the unit as I take it apart (never to be recovered) – the bike is then unridable. My only answer: buy a new item of the same model and wait until it arrives, then take it apart to figure out the process. Once I have that, I can be sure that I can get it back together or replace any broken or missing bits.
There are a lot of webpages and vids of "How to change the bike cables" but none of them showed the same model as I have or dealt with any of the problems I had, which is why I am posting this here. They all make it sound so quick and easy - but it isn't.
That's it for now. I hope any cyclists out there can gain something from my experiences trying to do my own repairs. I could have taken the bike to a shop and paid plenty to have someone else do it - but there is a problem: I don't own a car so how do I get it there? - and really, I want to do it all myself.
