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I need to replace the rear Shimano XT 7100 derailleur what broke in two at the base. It is attached by the single screw only but there is a metal pin fitted over the tip of the gear shifting cable. This pin is too thick to pass through the tiny hole in the derailleur where the cable runs through. The cable cannot be separated from the derailleur.

What is the standard procedure for this pin now? It seems possible to try cutting the cable (will be shorter?) or the (broken anyway) part of the derailleur (can I cut it easily enough?) or doing something to remove the pin (how?). If I cut the broken derailleur, the pin I think may prevent from installing another one.

3 Answers 3

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The "metal pin" is a crimp-on cover that stops the individual wires from splaying out and making a mess.

You might be able to yank it off with pliers, or you can use cable cutters to remove the cap by cutting the cable just as it enters the crimp. As per photo, there will be a kink in the cable which can make re-threadding difficult.

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Your other option is to fit a new shifter cable instead. The inner cable tends to wear over time at the shifter end, so straight-up replacement of a consumable is reasonable. Some cables acquire rust which makes shifting harder, again replacement can improve shifting.

When you fit a new cable or refit the old one, put a fresh crimp cap on the cut end. If you don't have one, you can use tape or heatshrink, or solder or superglue to hold the individual wires together.

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    And if you don't have any of those crimps on hand, they're available on AliExpress for $3 for a pack of 100 shipped to your mailbox.
    – MaplePanda
    Feb 1, 2023 at 1:59
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    Heat shrink tubing is a good option for me as I have the tubing and heat gun.
    – nightrider
    Feb 1, 2023 at 8:23
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    Old spoke nipples works well as crimps (I've got a bag of crimps somewhere but old nipples seemingly everywhere after a couple of wheel rebuilds
    – Chris H
    Feb 1, 2023 at 11:17
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    You might be able to yank it off with pliers First squeeze it with the pliers with the flattened axis of the crimp-on cover perpendicular to the pliers' jaws. That should force the crimped cap to loosen its grip on the cable some. Pliers with small teeth on the jaw surfaces will work much better here. Smooth-jawed pliers will allow the cap to rotate when you squeeze, possibly making the cap tighter. Feb 1, 2023 at 13:47
  • + 1 vote for solder because you can rethread the cable through the housing easily, which I had to do multiple times when switching handlebars. Crimps leave the end of the cable frayed so you can't push it through the housing without making it worse. I haven't had much luck with superglue, but it's the same concept. Also, if you cut the cable to remove frayed ends use a dedicated cable cutter like Park tools makes. Wire cutters will usually make it worse.
    – Rich Moss
    Feb 1, 2023 at 19:35
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By far the best option is to replace the cable. They are cheap and the performance does degrade over time. When replacing a derailleur its false economy to skimp on the shifter cable (I would do outers and inners, but inner only is better than reusing the existing inner.).

If you want to try and reuse the cable, you will find it best if you cut off the end cap. I would drop a dot of superglue on the cable to bind the strands,and cut with quality cable cutters. If you do not have the cable length to do this, pull the crimp off.

Don't bother cutting the derailer - as you have identified, the pin will prevent you installing the cable in the new one.

The pin is not strictly needed. It is there to prevent the cable fraying and protect you from the sharp end of the cut cable. I have dropped a blob of glue on the cable end when I ran out of cable end caps, and it lasted the life of the cable.

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I have a Sora derailleur, and have been able to get the cable out without removing the crimp (I trashed a derailleur just after changing the cable, which had used my last spare).

  • First you need to remove the pinch bolt (that grips the cable) entirely. See how it comes apart - you want to get the tab washer back in correctly.
  • Then unscrew the barrel adjuster all the way. The crimp should fit through the hole left in the derailleur arm. If not, it will be close and fixable by squeezing with pliers or filing the widest part.
  • Remove the barrel adjuster from the new derailleur, and swap the derailleurs on the frame.
  • Thread the cable into the new derailleur, fitting the old barrel adjuster. You might be able to just loosen the pinch bolt, or you might have to remove it.

If yours looks like the case in Criggie's picture, I'd cut the cable about 1cm shorter, as you've got the length to spare. Bike shops rarely cut it as short as possible, as that makes initial setup of the derailleur harder.

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