I'm having a problem with the cable for the rear gears on bike when I shift gears the cable becomes extremely slack to point where it won't change gears.
This happens when I'm on the second front spocket and when I change to biggest spocket (3rd) I can't shift past a certain point as the cable becomes extremly taunt.
I've tried to adjust the cable on the back derailer pulling up the excess slack when it a lower gear but I'm unable them to go to the lowest three gears.
Do I just need a new cable then or is there an adjustment point I'm missing? The front gear selector works fine, the cable does slip a little when changing gears.
My bike is a Trek 4300, 24 speed.
Hopefully, this makes sense.