Hi all. I have a 9-speed Dur-Ace rear derailler. I can use the 8 outer sprockets, but every time I want to use the 23 (inner most sprocket), it keeps slipping back to the 21.
Collumbo - Shift to 23 but stop turning the crank before it slips to 21. From the back check if your derailleur pulleys are lined up properly with gear (23), chances are they’ll be leaning towards 21, to correct this adjust the derailleur cable knob (the adjuster knob where the cable goes into the derailleur) counter-clockwise till the two pulleys are aligned (forming a perfect vertical line) with 23. If you adjust the derailleur cable knob and the derailleur stops moving towards 23 you need to turn the L-Screw counter-clockwise to give the derailleur more space to move inwards (towards 23).