So, from where I sit, my kid is 20 now, this dude has nailed it.
What we need to come up with is a life-sized remote-controlled bike. That way we could put the kid on it and play with the controls-using their wealth of youthful zeal and limitless energy to handle the punishment, whilest taking the bars and,via a remote camera, steering them to the fast lines.
That way they could experience the scraped elbows and busted knees and we could still swig a beer and tell them 'how fast we was' and get a buzz.
(Hang on-that almost sounds like being a passenger
)