Niner AIR 9 2-Star SX Eagle Bike: ELEVATE YOUR RIDING. If a cross country bike met a trail bike out in the woods, they fell in love and had a child, what would that bike be? How about Niner's new AIR 9? The perfect blend of cross country quickness mixed with a rowdier attitude. Run it geared. Run it singlespeed. Comfortable enough for all day riding and quick enough to pin it at the races, the new AIR 9 handles what you throw at it. Genetically engineered? Maybe not. But it sure is fun to ride.