Hello, apologies in advance if this is an easy answer.
I've been trying to get my rear derailleur working properly, but am just getting frustrated. The H, L and B screws are all in line. I have the tension as tight as I can get it on the cable, and the first couple of shifts work smoothly. Then, at about the 3rd (or 4th) cog, it hesitates. I'll then use the barrell adjuster to tighten until the chain jumps up a gear. After that, the cable is too tight, and if I shift down to the smallest cog, it won't shift past the second smallest.
My cassette is new, my rear D is fairly new (and straight), and my cable is brand new.
Any help is appreciated - I don't know what's causing the trouble.