I have 1400 miles on my 105 shifters . They work almost flawlessly except for the occasional
problem with the front DR. It only happens about once every 3 or 4 hours of use. It gets locked up on the big ring and won't downshift. I'm running a 39 - 53 on the front and 12 - 25 on the back.
When this happens I have to stop and yank on the cable and the FDR before it pops free. The FDR is not making contact with anything. It just seems to get jammed. Everything is clean and free of dirt and debris. My guess is cable stretch, but the fact that it shifts perfectly has me wondering. Any ideas?