This alertness has only come about by your extended (maybe) extensive (yes) miles or kilometers spent together in the saddle. Your ride-or-dies have your back, or at least we’d like to think so, because of the times you’ve had theirs. Over the years, in all manner of cycling situations — riding to and fro, up the same hills, through that same cemetery loop, plotting new rides, pointing out potholes, handing off extra snacks, changing each other's flats, or chiding each other from the sidelines — you’ve built a familiarity, an acumen even, that lets you roll together seamlessly.