Traditional beliefs would tell you that a feathery cross-country bike would be fragile and overly twitchy for all but the most experienced of pilots and professional racers. We're here to say you can have your cake and eat it too, at least when you're racing on the Santa Cruz Highball Carbon CC XO1 Eagle Reserve Complete Mountain Bike. Now don't get us wrong, we're not going to tell you this newest generation of Highball is going to be a worthy replacement for your trail bike, but it will radically shift your preconceived notions of what a stupidly lightweight cross-country bike is capable of as you fly past slow climbers and lap race courses with higher levels of speed than you ever thought possible. As we've seen year after year, Santa Cruz always manages to push the envelope in the design of their bikes and this third-generation Highball Carbon 29er is no different, weighing a half pound lighter than previous versions in their high-end Carbon CC lay-up. You read that right, the newest version of the Highball Carbon CC 29er is a half pound or some 200 grams lighter, dropping the frame's overall weight to just over two pounds, which is absurd when you think about it. Santa Cruz's composite engineers achieved this absurdly low weight through a meticulous application of carbon in zones critical to stiffness and structural integrity, trimming the bike down in all other areas for the utmost in weight savings. Because the Highball had the reputation as being one of the stiffest bikes in Santa Cruz's line, the engineers had a few tricks up their sleeves in muting trail chatter and excess vibration from this third-gen model. Low-angle seat stays meet the seat tube just below the top tube junction, plus there's a bridgeless seat stay to absorb incoming vibration over rugged race courses. Santa Cruz then uses a 27. 2-millimeter seat post diameter to impart even more compliance, so you don't feel every terrain inconsistency in your lower back for days afterward. Althou...