Former grand prix star Randy Mamola was a busy man at the US Grand Prix weekend - taking no less than thirteen lucky passengers around Laguna Seca on the back of the Ducati Desmosedici two seater.

The passengers included TV stars and actors, an Olympian, a Fiat heir, a Motocross world champion and a current AMA Superbike star. Here's what each had to say after their once-in-a-lifetime experience:

"Oh my God, that was awesome, just insane! It was the most terrifying thing but at the same time it was the safest I've ever felt on a motorcycle, if that makes sense!" - Actress Catherine Bell, from 'Bruce Almighty' and TV series 'JAG'.

"Man, that was the most terrifying, most beautiful thing I've ever done in my life, except when my ass came up off the seat over Turn One! I felt like I was in a video game, but the amount of energy I expended over two laps was amazing, so I can't even begin to comprehend what it's like to actually control one of those things for 30 laps" - Sal Masekela, presenter of extreme sports TV show.

"That was ridiculous fun, oh my gosh, it was indescribably good. And you get a much better understanding of what these guys do, so I will be in awe when I watch the race tomorrow" - Double Olympic swimming gold medallist Amanda Beard.

"That was 100 per cent pure adrenalin, I've never felt so good. For someone who gets turned on by engines as I do, that gave me an emotion I've never felt before. The whole thing was amazing" - Lapo Elkann (top picture) Fiat heir and motorcycle racing enthusiast.

"I've ridden round here on my 748R but it wasn't even the same track on this bike. I thought I'd be going round going 'woo!' but it was more like, 'oh my God, oh my God!' I was so exhilarated I was shaking, it was much more intense than I had imagined" - Cindy Knauss, from Socal Ducati, a regular track-day rider at Laguna Seca.

"That was unbelievable, I couldn't believe how fast he went. He was sliding the bike, it was frightening but I loved it, it was the best. The power of a MotoGP bike is just amazing, it really starts to pull from the middle of the straight, where a Superbike is flattening out, that's what a rider dreams of!" - Ben Bostrom (middle picture) former World Superbike rider and AMA Superbike champion, currently rides for Ducati in AMA SBK.

"Dude, that felt like I was making love to a lion! Holy cow, you know how time slows down in an accident? Well, that felt like an hour or two. I ride track days but that wasn't even in the same universe, it was totally amazing" - Dax Shepard, Hollywood actor, most recently starred in 'Zathura'.