I have done that road (Tail of the Dragon) on those bikes (1800 Goldwings) two up. I wasn't as fast as those chaps in the video, but I was keeping up with sportsbikes (lots of these American lads have never seen corners

) and cars were pulling over to let me pass. Not to denigrate what those boys are doing, but Goldwings
do handle vastly better than most people think/you would imagine by looking at them. Even so much that you can swiftly alter your line mid corner, when some prat in an S2000 nearly kills you and your pillion by skidding down hill and crossing half way into your lane (if I'd been in the car, as I was the next day, it'd of been a head on, no two ways about it).
It's a 30 limit throughout and the police have a policy of prosecuting anyone doing over 50, but 50 was plenty of speed for most of the corners. To anyone considering doing it, it was well worth it, but I'd like to try it on a 650 adventure bike next time (fastest chap I saw whilst I was there was on some mid sized supermoto).
Oh and I managed to bottom it out twice. Good thing it was a hire bike, it didn't sound nice.