Two of the new exciting road bike frames released by Rock Racing for 2012 are the X-3Si and RX4Si. While the X-3Si uses a combination of T800 and 3K carbon, the RX4Si utilizes a mix of T800 frame and a 1K weave carbon outer lamination.
Both the 2012 Rock Racing X-3Si and RX4Si Road Bike Frames weigh in at 1000g. For the X-3Si frame, custom sizes and Di2 wiring ports are optional while a seat mast is not available. It also gets an external cable routing as well as a little less shaped frame.
On the other hand, the standard version of the RX4Si frame comes with an internal brake and shift cable runs. For this frame, custom sizes are available while Di2 wiring ports and an integrated seat mast are offered as upgrades, as well.