Originally Posted by
damonwang
My mistake was asking for an implementation instead of a solution. Let
me back up. I want to shift quickly and then get my hand back on the
handlebars. The longest part of the shift is trimming the derailleur. I
was supposed to learn the stops with time, but after a year I'm still
fumbling around every time feeling for the shift. How can I shift more
easily?
Unless you can get an indexing system that happens to work with your setup, friction is going to be it. I'd guess that your really want to be able to feel the shift happen. When I was using downtube shifters, I'd move the levers untill I felt the gear had changed (you can feel it through the shifters). Bar end shifters might make that easier for you. Oddly, it might be faster (overall) if you shift slower.
Indexing is related to the distance between the cogs. The distance between the cogs in a 5 speed cluster is too big. This might be where you get stuck with regards to your bike being too "old". I have no idea if there was ever indexing for 5 speed clusters.