Modern Cars and Trucks Suck, More People Will Switch to Bikes 

As cars and trucks become more overpriced and less reliable, the used auto market will be filled with the garbage that is coming out now. More electrical problems, more complex components, more expensive to service, and overstressed engines will lead people to seek alternatives. Much like in Asia and Europe, people will increasingly look for alternate vehicles. Also, with lane splitting becoming more mainstream, I predict more motorcyclists on the roads in the states in the next 10-20 years.