I have a bike with a Nexus 3 hub gear. Yesterday the shifting got out of whack, when set to gear 2, it was actually in gear 1, gear 3 was 2, and so on.
I looked up how to adjust it, and found that I have to rotate the adjustment knob until the yellow mark is between the lines in gear 2, after loosening the locking nut, as seen f.ex. here:
The problem is that when I rotate the adjustment knob (as in 1:13 in the video above), the yellow mark does not move. The yellow mark stays in the same spot even if the adjustment knob is all the way in or all the way out. So I cannot adjust it to be be between the lines. What could be happening? Am I doing something wrong or is my gear broken?