You won't find an X Large Les 27. 5 Carbon Mountain Bike Frame for the same reason you won't find an X Small Les 29 Carbon. Pivot smartly packages smaller wheels with smaller frames and larger wheels with larger frames. A concept that, oddly, seems to escape other manufacturers. And when proportionally correct frames and wheels are matched up to Pivot's extensive composites program, you can be sure the LES boasts a smooth ride and responsive handling. Add to the picture a 12x142mm thru axle, tapered head tube, and BB92 bottom bracket shell, and it's clear Pivot hasn't cut any corners. However, the most significant example of this is the hardest to see the fully compacted carbon fiber that's used in the frame. By optimizing the compaction, Pivot removes any unnecessary resin, which minimizes weight and optimizes strength. The tube forming is of particular importance as well, because it dictates the ride quality of the frame. Accordingly, areas like the chainstays and down tube, where stiffness is paramount, have been built as large as possible to fight deflection. On the other hand, the seatstays have been flattened and feature a slight bow, which allows them to bend under load, smoothing out the ride. This ensures the Les 27. 5 rides beautifully over rough terrain, while remaining stiff when you get on the pedals. The Pivot LES 27. 5 Carbon Mountain Bike Frame also features details like custom molded, impact resistant stays and a down tube guard. It's available in four sizes from X Small to Large and in the colors Green, Matte Blackredwhite, and Matte Blackblue.