It seemed natural to take the Pivot Mach 5.5 carbon X01 Eagle to the top of Burke Mountain in Vermont’s Kingdom Trails for its test run. Filled with rock gardens, gnarly roots and epic berms, these trails were made to rip and huck at speed. Is it a cross country bike, progressive trail or all mountain? Regardless of what you call it, the Mach 5.5 turned out to be the perfect tool for the job.