Wednesday, May 19, 2010

Help! Internally Routed Cable

I want to get rid of the downtube shifters on my Trek and use a pair of thumb shifters that I've had stashed away for a while. The problem is that the rear dérailleur cable is internally routed through the chainstay. Does anybody know an easy way to replace the cable?

The cable enters from the bottom of the chainstay here...

...and comes out here.


  1. maybe try to attach fishing line to the cable and then pull it through?

    on some applications sewing thread and a vacuum cleaner can also work.

  2. Since there is already a cable there, attache the fishing line or string or whatever to the cable end (electrical tape should do the trick; use a LOT of overlap between the string and cable, like six inches, then wrap with tape). Pull the cable through, pulling the string with it. Attach the new cable to the string and pull it back through the other way. Easy-peasy. If you don't get what I'm saying based on my description, let me know and I can probably stop by and help.

  3. This is how we get a dynamo light cable through a frame. A similar method may work for brake and gear cables:

    Get use a thread with a small piece of metal (we used a bit cut off a paper clip) thread it through the hole and then turn the bike in the stand so the thread falls vertically inside the tube to the exit hole.

    Get the magnet and hold it over the exit hole until the piece of metal attaches to it.

    Pull the magnet out, so it pulls the piece of metal and thread with it.

    Tie wire to other end of thread (making this knot small enough is the hardest bit)

    Pul thread and cable through hole. slowly.

    Hope it helps...

    get a magnet to attract the bit of metal

  4. WELL, you COULD donate the bike to me and I'll tell you how I did it as soon as I get it figured out!

    Seriously, I think using the line approach has merit, and I also notice there are a few items on bikeforums AND on Youtube. Both are worth a look! Do NOT read what Sheldon Brown had to say on internal cable routing.

  5. I solder a cable to the end of the old one in the bike pull it through and then do the same with the new one,pulled it through and cut and ferruled the end.

  6. Thanks guys. As always you provided some interesting answers. I could just check Sheldon Brown's site or go to Bike Forums, but I prefer hearing from you guys. You're much more entertaining.

  7. Doohickie-Gosh, I'm just trying to express my feelings!