Great place to visit! Was out there yesterday for the unveiling of a Lotus X which had just been restored. Amazing place, tons of bikes plus the largest Lotus collection in the world. If you make it for one of the major events like Indy, AMA or Vintage Festival they have the basement open and you can walk around and see the stuff down there. During the Vintage Festival they have demos and talks by bike restorers. If you make the Vintage Festival the Friday night dinner - Motorcycles by Moonlight is a great event and they have some amazing folks - it's pricy but a great event.
My plug for the museum.