I know this thread is a bit old, but I wanted to chime in on the dual valve stems just so people know...

Those wheels most likely do have two valve stems especially if they are lightweight wheels meant for motorsports.

When I raced autocross one of my good friends had a set of Kosei's with dual valve stems, the purpose was to purge the tire with nitrogen, which is lighter than air, and supposedly has better characteristics as far as temperature expansion and such.

Sorry about the bump!