Originally Posted by
Russ Roth
Doubtful the shifter doesn't work right. I've assembled thousands of bikes with cheap low end shifters and if they were shimano shifters I never had one that failed to work. It can happen but it would be incredibly low on my list. Often if a shifter was replaced and the shifting was crap or a new build with the same problem, it was due to a small kink in the cable typically up near the shifter. They love to kink just inside the barrel of the shifter and while it might look like it should be nothing the internals of a 4mm housing is tight enough it can matter. Pull the cable completely out of the housing and look for a very slight bend, that's probably your culprit. Often it allowed for decent but not great upshifting and would feel like the shifter was a little tight to push but was more evident on the down shift with slow downshifting and noise.
The shifter was next (and last?) on my list to "get up close and personal". Your suggestion about the cable makes sense and I'll check that before dealing with the shifter directly. That could explain why I never felt the shifter was quite right (it was close and it seemed like shifting was fairly consistent, as in no noise, but I sensed there was something off) and it was the most recently replaced. I have had a "sticky" shifter in the past due to gunk on the cable/in the housing but it was very obvious that something was happening. This is a much more subtle (both insidious and frustrating) symptom
Curious if you ever ran into a problem related to the cable guides (not housings). I have one mounted on the bottom of the bottom bracket housing that supports both the rear brake and rear der bare cables.
Thanks much for the insight. I can only hope
Cheers....