I wonder if the ramps and motorcycle are better or safer than what Evel used. They said the motorcycle is Indian and it does have big tires. The fountain jump looked the easiest of all three, probably due to the ramps. The ramps were so big I could hardly see the fountains.
I think you nailed it. The engineering of the ramps is what made the difference. And as someone else said above, this was probably all computer modelled to build in a significant margin of error. Everything advances.