The Sirrus X offers an unmatched blend of comfort, efficiency, and agile handling, excelling on pavement, gravel, and any terrain in between. COMFORTABLE, SMOOTH, AND EFFICIENT: The Sirrus X delivers the smoothest ride in its class. Featuring wider, confidence-inspiring tires, a slightly more upright riding position, and a super intuitive one-by drivetrain. RIDER-FIRST ENGINEERED™: At Specialized Bikes, each frame size and geometry is individually designed rather than simply "scaled down." For every size, tube lengths and diameters are assessed for optimal stability, weight, and responsiveness. The goal? No matter what frame size you ride, we ensure you have the best riding experience in the world. COMFORTABLE: Industry-leading weight, exceptional pedaling efficiency, and flexible handling combine to offer almost telepathic riding qualities.