I'm doing a modern conversion on an old steel frame, and it's working out quite nicely. I have, however, run into an issue with 11 speed indexing. A few of the cogs just won't index, but the same components work fine on my other bike. The rear triangle is 126, so I'm spreading the rear triangle to insert the wheel. In theory, this would mis-align the derailer hanger slightly, which must be enough to impact shifting negatively. It's aligned well enough for 126 because it indexes fine with a 126 wheel, and works fine with a 130 wheel and 8 speed. My guess is the tiny difference is throwing off the shifting for 11 speed. By the same thought, my plan to cold set and align the rear end to 130mm would solve the problem, right?