If I understand Lumpy's meaning, I think what the man or woman in the street would recognise:
Any Harley (thanks to Hells Angels, American Chopper etc)
BMW GS (thanks to Ewan and Charlie Longway round the bend stuff)
Old British bikes (a few on various TV programs/Films but most wont know what they are)
Vespa or Lambretta Scooters (as above)
Non Bikers wouldn't be able to tell the difference between a 400/4 and a Z1 and to joe public most modern machines are just brightly coloured noisy death traps