Got on my bike the other day and it wouldn't shift down to the granny. This hasn't been a problem since last adjustment, some time last fall. Same with GF's bike. AFAICT the only change is the ambient temperature - some 20-30°F warmer.
Metal expands as it heats, so it makes sense that the cable would be a little longer. But this is an issue I've never seen addressed. Anyone thought about it?