why do my pancakes (crêpes) take such a long time to cook?
If it doesn't contain eggs, or at least something that serves as a substitute for eggs, it's not a crepe. Crepes cook quickly because eggs need very little time/heat to set up. Like justkt said, what you've described is a tortilla. I'm not exactly sure how or why a tortilla "sets up" (if you can even use that term for a flatbread), but it's a completely different mechanism than cooking eggs, and takes a much longer time.