Rear Derailleur Adjustment

[RobertLee]

I installed a new cassette and chain. But I can't make the rear
derailleur adjustment required for clean shifting. If I tighten the
cable, I can't shift from the largest cog to the next-to-largest cog..
But if I loosen the cable, I can't shift from the smallest cog to the
next-to-smallest cog.

I have a Shimano 105 rear derailleur and a Shimano 12/28 cogset on
a 1992 aluminum Trek 1440.

 

[Nate Knutson]

You didn't mention whether the new chain is technically compatible with
the cassette, but assuming it is and that there are no other
compatibility issues, the main possible causes for this are limit screw
misadjustment, cable friction, derailer pivot slop, and derailer hanger
misalignment. The most likely limit screw problem is that your high
screw is too far out.