Hi,
No, the Valhalla uses the same 50Hz pulley on U.S. LP12s. It takes 60Hz 120V and synthesizes it to the 50Hz 85V AC required to drive the LP12 motor. It's just a matter of changing the fuse to the proper slot, and no pulley change required.
On the other hand if you own a U.S. Majik LP12 and plan to upgrade to a Valhalla or Lingo 1-3 then you will need the 50Hz pulley since the Majik LP12 uses a 60Hz pulley (smaller).
I've done a couple of upgrades on the Valhalla and have seen the alternative fuse position for the USA.
I'm in the UK so all 230/240v
I've just been reading "Hi-Fi AF" a blogger who has gone down the Mober/aro/keel/kore/Tiger Paw routes....not read it all yet but it looks an interesting read.
I'm not in any mad rush to upgrade yet, but its always in the back of your mind with an LP12.