I have just ordered a OneUp Components 42T sprocket and a Race Face 30T Narrow/Wide single ring so that I can convert my 3x10 drive train into a 1x10. This means that I'll be removing the front derailleur all together. I have a carbon frame with internal cable routing so once I've removed the shifter cable there will be open "ports" in the frame. Is it important to plug these ports? What might happen if I don't plug them? There is one where the cable enters at the top of the frame, and one under the bottom bracket where the cable exits.

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  • Great work going to 1x10, is there a way you can leave the cable in the ports in case you decide to go back to 3x10 (or whatever the future holds) or sell the bike? From what I've read it's a PITA to re-cable through internal ports.
    – DWGKNZ
    Jan 28, 2014 at 23:59

2 Answers 2


If it were me, I'd do it ,but I don't think it's necessary. Frames of all materials will have drain ports in them. My carbon Focus road bike,for example, will have water pouring out of. Frame when held vertically after a very wet commute, this is how it was designed. Metal frames have holes to allow welding gasses to escape, water can drain from these. So,plug them if you can, but if not, don't worry about it!

  • 1
    When I posted this question I also contacted Rocky Mountain to see what they had to say. Your answer is pretty much what they said. It would be best to plug the top one (they even make a rubber plug specifically for Element frames) but the one under the bottom bracket is less important and should have some gaps to allow for drainage. Jan 30, 2014 at 18:44

I would plug them. If left open you will have the chance of water ,dirt, etc, inside the frame. The water and grit will eventually make its way to the bottom bracket. Even if the bearings are sealed it will still get on the threads of the bearing shell or threaded inset potentially making it difficult to remove.

  • And even sealed bearings won't last forever if suspended in water, especially if there's salt involved from winter riding.
    – arne
    Jan 27, 2014 at 12:17
  • Water will make it's way in regardless, if the bike is used much in the rain (or left out in the rain). The water needs a way to get out. Jan 27, 2014 at 13:10
  • @DanielRHicks, then what is your advice?
    – Vorac
    Jan 27, 2014 at 14:26
  • 3
    @Vorac - Don't seal the frame up tight. There need to be vent holes, at least, and in some cases the cable holes are serving this purpose. Try to "seal" to prevent water entry but not totally block airflow, especially with the lower port. Jan 27, 2014 at 15:23

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