Mach 5.5 Carbon Pro XTR Live Valve Reynolds Complete Mountain Bike
The Pivot Mach 5.5 Carbon Pro XTR Live Valve Reynolds Complete Mountain Bike features modern geometry, carbon frame construction, and suspension technology that is rivaled by few on the market. Pivot refers to it as their quintessential trail bike, but in truth it's just damn fun and insanely capable. It gobbles up anything in its path on the descents, while maintaining the climbing prowess DW-link suspension is known for. It also happens to be one of the first bikes with Fox Live Valve electronic suspension fully-integrated into the frame, a game-changing technology that senses terrain changes and automatically adjusts your suspension to match them, with a .003 second response time. It sounds complex, but in truth it simplifies your riding as there's no need to worry about switching between suspension modes. Instead, the suspension does it for you in real time, balancing ride quality and pedaling efficiency for the best experience regardless of the trail.
As the name implies, the Mach 5.5 has 5.5in of rear travel provided by the DW-link suspension platform. DW-link is a world championship proven suspension design invented by Dave Weagle. DW-link separates itself from other dual-link designs with its impressive square-edged bump compliance, attributable to the initial rearward axle path. It's also fully active under braking, keeping your rear tire glued to the ground in rough terrain instead of chattering, and allowing you to brake later into corners to carry more speed upon exiting. It's paired with a 160mm Fox fork up front, letting you to smash over everything in sight with the prowess of a full-blown enduro bike. The difference in travel between front and rear gives you a bit more pedaling efficiency, with extra plushness up front to soak up chunky rock gardens and bigger hits.
The bike industry is ever-evolving so it makes sense that the Mach 5.5 sees long, low, and slack geometry that's right in line with other progressive trail bikes. A 66.5-degree head tube angle provides stability on descents and high-speed sections, without letting the front-end wander on sustained climbs or tight switchbacks. The long reach and front-center measurements further improve stability, with short 16.9in chainstays to enhance maneuverability on narrow, winding singletrack. A low-slung top tube and short standover height let you to lower your center of gravity for optimal control on steeper descents and tight corners.
Pivot carbon frames have perhaps the lowest warranty rate in the industry, at less than 2%. The strength of their frames is attributable in part to the high-modulus carbon they use for all frames, but also to their proprietary hollow core internal molding process that yields consistent, high compaction with extremely tight tolerances throughout the entire frame structure. The resulting carbon frames are correct and precise right out of the mold, with no need for touch-up work to fill voids or imperfections. The rear triangle allows clearance for 2.6in tires, a nice benefit for riders that like the extra grip and compliance of high-volume trail tires.
This build seamlessly integrates Fox Live Valve suspension. Electronic suspension has been around for years in automotive racing, but it's a pretty foreign concept in mountain biking. In order to quiet the skeptics, Fox spent three years developing and testing Live Valve before they released it, making sure the performance and reliability were on target. The Live Valve system uses accelerometers on the fork and rear triangle to sense impacts and changes in trail gradient, with a microprocessor (Fox calls it the Controller) mounted near the rear shock that houses a third accelerometer and the rechargeable battery. Using these sensors, the Controller measures the terrain at a rate of 1000 times per second, and activates solenoid valves in the fork and shock that open in just three milliseconds, going from a firm pedaling platform to wide-open plushness almost instantaneously.
The Live Valve system defaults the solenoid valves to the closed position, the equivalent of running your fork and shock in the firm pedaling mode. When the system senses an impact it opens the valves to allow smoother suspension action—improving traction, bump absorption, and overall ride quality. After a preset timer, the valves return to the closed position to regain pedaling efficiency. Each bump resets the timer, so when you're charging through rock gardens or sustained sections of rough trail the suspension stays in the open position to better mitigate impacts. The accelerometers also sense when you're going downhill, so if the bike is angled more than 6-degrees downward both the fork and shock remain open. When climbing, the Controller will open whichever suspension component feels the impact and then return to the firm position immediately afterwards, unless another impact is sensed. For flat trails, an impact opens both the fork and rear shock, with a delayed timer to account for successive impacts, but not so long to cause the bike to wallow in its travel when you start cranking hard. Should you go airborne, the system opens both the fork and shock to absorb the landing, returning to normal once the bike is rolling smoothly again.
Fox claims you can get about 16-20 hours of ride time from the Live Valve system. If you run out of battery while riding, the system opens the valves so you can use all your travel without a harsh ride. It's important to note that Live Valve only affects the low-speed compression circuit, changing the overall stiffness of your suspension. Rebound settings and air pressures are not affected, so you set your sag and baseline settings in the same manner as normal air suspension. If you're still skeptical about Live Valve, there's always the option of shutting off the system entirely, rendering your suspension the same as a standard setup. With a minor 260g weight penalty for the full setup, the only hurdle is the price.
This kit comes with a mix of Shimano XTR and XT drivetrain components, providing smooth shifting at a low weight. Reynolds carbon rims deliver precision handling and superior durability, and are laced to high-engagement US-made Industry 9 hubs for quick acceleration. To arrest that momentum, Pivot includes Shimano XT-M8000 brakes, known for their quick bite and superior stopping power.
- A progressive trail bike with high-end drivetrain and wheels
- 5.5in of DW-link travel climbs well while remaining fully active under braking
- 6.3in travel fork maintains composure on the rowdiest descents
- Fox Live Valve electronic suspension adjusts compression in real time
- Live Valve switches between firm pedaling and open plushness in 3 milliseconds
- Long, low, & slack geometry provides stability for descents and high-speeds
- Sturdy carbon frame comes with a 10-year warranty & reliable oversize bearings
- Kit includes Reynolds carbon wheels & Shimano XTR/XT drivetrain for reliable, lightweight performance