Originally Posted by
pepperbelly
Shimano Flightdeck shifters, Ultegra groupset. New condition.
When I push on it I can see the cable housing flexing.
Can the derailleur be sticking?
New condition flightdeck?...that's probably 15 years old or more. Ultegra 9sp, I'm guessing.
Odd that they would be new condition.
Undo the cable pinch bolt at the rear derailleur so the cable is slack. See if the shifter then clicks without any tension. That is always my 1st step to determining what's wrong.
If it clicks as it should, then you know the shifter is fine and the issue is elsewhere(cables, housing, rear derailleur). If the shifter doesn't click as it should, you know the issue lies with it.