I found out last night that my Grande came with pedal arms with two different size threadings on them. One side was the standard 9/16" crank size, and the other was 1/2" BMX size. I've never seen the 1/2 size before!
Did those come standard on any bikes? I'd really love to find another one (left side) so I can run these incredibly ugly Primo BMX pedals I have kicking around