Well this is embarrassing, I just Googled the Odyssey Twisted pedals I got used from the LBS near here, and they're absolutely 9/16" pedals...The mechanic here who sold them told me that they were 1/2" and would fit my Langster 'for sure'...My fault for writing that down and banking on his being correct. But now this cringe-worthy discovery has opened up the whole world of choices for pedals. Many Thanks for the help.