If you glance at the specs, you'll notice that the 2016 Niner Air 9 RDO Mountain Bike Frame is roughly 100 grams lighter than the previous version. This was accomplished using Niner's Carbon Compaction System CCS. This process allows the Niner engineers to create tubing that is near perfect in shape and wall thickness, without wasted carbon or resin build up. Without the cushiness of a rear shock, Niner went to town to design a frame that not only dampens vibration and minimizes chatter, but also moves impact forces to the larger and stronger areas of the frame so you can take a hit from rougher trails. The bottom bracket is designed for a PF30 and your pedal power is transferred to the rear drivetrain via the same chainstays as the previous version. The difference is that Niner has added a 12x142 Maxle to the rear dropouts. The oversized downtube keeps the bike holding tight to the line you choose, and its clearance allows for tires up to 2. 4in wide.