If you’re into extreme sports, you’ll dig this. If you’re into watching insane people doing insane things from the safety of their webcam, you’ll love this. Welcome to Valparaiso Cerro Abajo, the premier downhill bike race of the year. It doesn’t necessarily get as much press as others because the entrants are normally fewer than other downhill races. Once you see the videos, you’ll understand why. Unlike most races, this is on a very “loose” track. The streets and sidewalks of Valparaiso, Chile, are not conducive to normal biking and are made more treacherous by the narrowing of the course, poorly-built…