Originally Posted by
FBinNY
The FD adjustment is most likely, especially since it started with the cable replacement.
Not exactly. At first, I thought the RD was skipping, so I swapped the RD, changed the cassette, and replaced the rear cable. As it turns out, it's the front that's the problem.
Originally Posted by
cny-bikeman
You are going about things backward. Diagnosis is not a matter of multiple choice, unless you want to spend all day trying each possibility.
The process of elimination starts with finding the options, and then eliminating them.
Originally Posted by
Jiggle
BB shot, frame cracked.
BB is about a year old. The frame is in good condition.
Originally Posted by
southpawboston
Fork's bent.
AAAAAaaaaaaaaggghhh!!!! Why didn't I think of that?
Originally Posted by
southpawboston
Here's another possibility-- there is not enough friction holding the shifter in place. I'm assuming the FD is friction shifting only. It's possible that in the large ring positions, the shifter has enough friction, but has a low friction spot where its position corresponds to being in the middle ring.
I actually had this problem with a Shimano 77xx series bar end shifter when mounted on a Paul thumbie mount. I had to torque the pivot bolt pretty hard to prevent the FD from slowly migrating toward the small ring.
I looked at this after you posted. I think it's OK. The front shifter is intact with no problems. The screw holding them on is tight.