Pivot

Mach 5.5 Carbon Pro X01 Eagle Mountain Bike - 2018

Building on the legacy of Pivot's renowned Mach 5.7 Carbon, the Mach 5.5 Carbon Pro XO1 Eagle Complete Mountain Bike pushes the envelope in terms of progressive trail geometry by moving the bike into longer, slacker, and lower territory. It slays everything the trail throws your way, from chunky, rock-impeded climbs to wicked descents with square-edge hits, sudden drops, and rock rolls. Pivot places it firmly into the trail category, with a secondary focus on all-mountain exploration. To be frank, we just call it "damn capable" and "stupid fun," satisfying the aggressive rider demanding their bike to climb like a goat and descend with unflappable confidence.

The Mach 5.5 Carbon retains the sought-after benefits of the DW-Link suspension platform, namely the ability to claw up the steepest, chunkiest climbs and soak up square-edges on the descent. Once you've reached the top of a long climb, 5.5 inches of rear travel gobbles up chunky rocks as you demolish technical terrain with speed. It's all party up front, with 6 inches of travel providing the confidence to smash over anything in sight, including sections usually reserved for longer-travel enduro bikes. The 20mm disparity between front and rear travel gives you a bit more efficiency for pedaling, with extra plushness up front for rallying across the rough stuff.

Seeing as how the industry is constantly evolving, it makes sense to see the Mach 5.5 Carbon with slacker, longer, and lower geometry to satisfy riders seeking a progressive trail bike that stays glued to the trail and retains stability at high speeds. The 66.5-degree head tube angle provides composure on high-speed descents, without being overly slack or wandering on sustained climbs with steep, punchy sections. Just a tick shorter in the front-end than the notoriously long and slack Firebird, the Mach 5.5 Carbon's longer top tube gives you ample cockpit room, which is especially welcome if you have a longer reach. This longer front end is complemented with snappy-short 16.93-inch chainstays, which provide extra maneuverability for cornering and climbing tight sections of trail.

A few key details make the Mach 5.5 Carbon a truly stand-out trail bike. Delving into its carbon frame construction, Pivot employs their proprietary hollow core internal molding process with an optimized lay-up of high-modulus carbon for the lightest weight possible. This method produces a frame that approaches the feathery feel of the Mach 429 SL Carbon, but with similar strength and stiffness to the enduro-bred Mach 6 Carbon. Looking at the rear end, both the seat and chainstays clear tires of 2.6 inches, which is a nice benefit for riders seeking the added grip and bump compliance of high-volume trail tires.

This particular build enjoys the precise shifts and plentiful low-end of SRAM's XO1 Eagle 12-speed drivetrain, complete with a 10-50t cassette for spinning up the steepest climbs. The FOX 36 Factory fork is impressively stiff for picking apart the technical lines and plunging into steep descents with confidence. The bike's equipped with 35-millimeter DT Swiss M1700 wheels rolling on 2.6-inch Maxxis Wide Trail tires for impressive traction and cornering confidence—all without the significant weight penalty of a plus-sized tire.