Originally Posted by
overbyte
Although the chain is on the left, you still pedal forward to move the bike forward, so the pedals screw into the crank arms in the normal way: on the right side, righty-tighty; on the left side, lefty-tighty.
So in other words both crank arms are "special" in that you can't use standard crank arms if you're worried about pedals loosening. I think that's what tk1971 was getting at with his question.