>>3911>>3912Some points: Going down hill is easy and less dangerous. Going up hill is hard. Granted, harder on a pedal bike going down hill than a dirt bike because no engine braking. But they could drag the rear wheel any time they wanted to cut speed. It isn't as dangerous as you think it is.
To the guy riding it's happening at least half speed and probably slow motion. Even more so if they got to run the course more than once. Which I'm sure they did. Even if you fall you aren't going that far before you stop and this course looks pretty safe compared to some of the places I've ridden. Has to be for insurance purposes.
Going uphill is much more dangerous because you don't have the option to stop. You're locked in from the moment you start up and if anything goes wrong it's going to hurt a lot and your bike is probably coming down on top of you.