Troublesome 7-speed STI adjustment (one click off top and bottom)
 

I know there are hundreds of threads out there on adjusting STI rear derailleurs, but I haven't found exactly my (probably trivial) "problem" and so it might be easier to just ask again.

Please don't laugh at my 7-speed 105 setup. It's on my 12 year old Air Friday (which also has a 3-speed internal Sachs rear hub). but I took it out of it's case for it's annual check up and before I pack it away for another year, I would like to get it shifting correctly.

I know the basics of STI RD adjusting: drop to smallest rear, click up to 2nd smallest rear, barrel adjust til just making noise against the 3rd, roll it back half a turn.

But here's my result (and please excuse my nontechnical terminology).
* Drop it down into the smallest rear.
* One Click up to the 2nd-smallest.
* Barrel adjust to noise point, then back.
* It then shifts smoothly 3,4,5,6... up to the biggest rear (#7).

* BUT then it needs 2 clicks to drop down to the 2nd-largest rear (#6).

* then it clicks smoothly down to the 2nd smallest (#2) but won't drop back into the smallest rear (#1).

So, I seem to be one index point off at both the top and bottom, even though I think I started the adjusting process off correctly.

any suggestions as to what I am doing wrong?

many thanks

Peter

possibly cable friction interfering with the "release" allowing it to shift to smaller cogs. But first, I'd just release some tension and see how it goes before I mucked around with the cables and housings.

that's a good suggestion. it has been a while since I replaced the cables and housing.