I adjusted my stem height the other day, and since then, the stem hasn't felt straight. I've attempted to straighten it a few times, but because I'm just eyeballing it, the handlebars don't quite seem right when I ride.
(I have similar problems when I try to straighten my saddle or brifters; is this hard for other people, too, or do I just have some sort of alignment-blindness? :)
Is there a simple way to make the stem objectively straight instead of relying on my subjective (and wrong) judgment?