I have a 1x Microshift Advent x system with Dropbars. I replaced the shift cable housing and cable and now it shifts perfectly, however it downshifts twice in the middle of the cassette. This did not happen before I replaced the cable and housing.

E.g. from gear 5 (21t) I will press the down shift button, and it will go to gear 3 (15t), skipping gear 4.

I have tried googling this problem but all I can find is about shifting up twice, but that is not what's happening.

1 Answer 1


This happens because there is not enough tension in the shift cable. After replacing a shift cable, it is very common that gear indexing needs to be readjusted.

To fix this, locate the barrel adjuster (either on your rear derailleur or shifter) and unscrew it slightly (1 click). Check if it solves the problem by trying to downshift from gear 5 to 4 again. If it still jumps over the 4th gear, continue unscrewing the barrel adjuster until it does not. Then, verify that you can shift without problems up and down everywhere on the cassette.

Once you get to an adjacent gear for every click of the shifter, you may still need to continue adding a bit of tension in the cable to make sure the chain is as centered as possible on the cog. If there is a slight offset, you may hear the chain rub on an adjacent cog.

  • Thanks for the reply! I tried this, but even when I increase the tension significantly (to the point that it wants to shift up even in the correct gear this still happens.
    – HristoM
    Jun 2, 2023 at 7:51
  • @HristoM did you pinch the cable on the rear derailleur exactly the same way as before? Otherwise, this may have changed the actuation ratio of the derailleur.
    – olliebulle
    Jun 2, 2023 at 11:35
  • I did use a slightly narrower diameter M5 bolt to anchor the cable. Could it be that? I believe I pinched it the same way as before.
    – HristoM
    Jun 2, 2023 at 13:18
  • @HristoM If the cable is pinched the same way as before it should be okay. If you feel like it, you can add pictures of the rear derailleur so we can see how it looks. At this point, I would also check if the derailleur's hanger and derailleur's cage is bent as this can also affect indexing. Also, make sure you used compression-less housing.
    – olliebulle
    Jun 6, 2023 at 14:02

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