Ok, this is more a vent than anything, but if my chain drops off my crank one more time, I'm gonna scream!!!
I just switched from a triple to a double, now I had my triple setup dialed in as I had it for over 3 years, and didn't change much, but I got the idea to switch to a double as I was rarely using the small ring, and I figured a nice shiny new bike part is always a good thing. I switched the crank, and bb, and left everything else pretty much the same, adjusted it all up, it's still not quite perfect (I have to replace the FD Cable as now i JUST have enough to get it over the fd) but I do have this cable and am planning on doing it this weekend.
My front der is a 105, and rear is dura ace, the 105 however is for a triple. Initially I didn't think this would be an issue, since I could just adjust the limit screws and make sure the cable was in the proper positions, and for the most part it hasn't been, but on a group ride last night I dropped off the top, out over my big ring. I wasn't even shifting the front, I was shifting the rear to the highest gear, and it just hopped off. The only thing I can think is I was pushing pretty hard, and with the new crank and higher tooth count in the big ring, my flex seems to be greater than it was and I think that's what pushed it off the ring.
I found a great deal on a NOS 105 double specific FD on ebay, so I ordered that, even though I don't think that's all, or heck, might not eve be some of the problem, but my current fd does have some wear, and for 25 bucks, ya can't go wrong, so that will be coming next week.
My question is, if it's a frame flex issue, I'm guessing I'm just going to have to tune it as close as I can, then go pound it up a hill in the worst gear and see if it stays on. UGH. Could be a long weekend.