Pivot Mach 5.7 Review

Pivot’s best selling trail bike was decided the moment the Arizona bike brand released the five-inch-travel Mach 5. By luck or design, it was a near-perfect blend of honest handling and cross-country efficiency. While the Mach 5 was designed to be a longer-travel XC/trailbike, the Mach 5.7, with its slack head angle and re-curved suspension metrics retains the efficient pedaling of its sibling’s position-sensitive dw-link suspension, but adds a new level of handling and confidence that encourages its pilot to stray deeper into the technical realm. Set up with Pivot’s Shimano XTR build kit, our medium-sized test bike weighed 25.9 pounds ready to rock with Shimano XT trail pedals. Expect to pay around $6899 for a similar build.

In profile, the Mach 5.7’s minimalist simplicity masks a number of innovative design elements. Its double-butted main frame tubes are rectangular profiled to put more metal in line with the frame’s highest loads. The deeply curved top tube provides a lot of stand-over clearance (26.5 inches for the X-small frame) and also eliminates the need for a separate strut to support the seat mast. Like all top trail bikes, the Mach 5.7 has a tapered head tube, so if you don’t agree with its 67.6-degree head angle, you can add an AngleSet and try a home-grown version.

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Placement of the dw-link pivots is critical and in the case of the Mach 5.7, the lower link competes with the front derailleur location. Pivot offsets the linkage bearings to the left and incorporates a direct-mount derailleur to solve the crowding there. Pivot uses a two-piece bottom bracket forging that captures the outside of the lower link. The hollow, welded forging enhances frame stiffness and with its wide-stance pivot placements, promises to extend bearing life. On the subject of bearing life, Pivot doubles two sealed cartridge bearings in each location to be sure that the suspension won’t waggle due to premature bearing wear.

Following the frame back to the Mach 5.7’s swingarm, Pivot redesigned the triangulated bracing between the seat and chain stays to provide clearance for 2.35-inch and larger tires, and then beefed it up with stiffer, C-section struts. At the dropout, Pivot’s burly replaceable derailleur hanger is designed to take a serious beating. Pivot did not outfit the Mach 5.7 with the new 142/12-millimeter through-axle. However, complete builds are set up with the 10-millimeter DT Swiss through axle system that works well with standard dropouts.


Those of us who believe that every bike requires a chainguide will be sad to see that there are no ISCG tabs on the Mach 5.7, but somewhat relieved to discover that Pivot offers a sturdy adapter that both clamps onto the bottom bracket shell and bolts to the frame. Pivot’s ISCG-05 adapter, and is intended for single-ring cranksets. Check it out here. For riders who want to build up a Mach 5.7 at home, Pivot sells the frame only for $2199 (including the Fox Kashima RP23 shock) in five sizes, from extra small to extra large, as well as specific women’s sizes. Colors are charcoal anodized (ours) and white, and either pink or baby blue as female options. Complete Mach 5.7s start at $3899 for the Shimano SLX build and top out around $6900 for SRAM XX and Shimano XTR options.

Pivot reconfigured the Mach 5.7 dw-link suspension geometry with a higher leverage rate and a flatter curve to feel a lot more plush in the mid-stroke and then consulted with Fox Racing Shox to tune its Boost-Valve RP23 shock to work in harmony. The result is a much smoother feel throughout the suspension travel with less ramp-up at the end-stroke. The changes in shock tune and suspension geometry, added to the fact that the Mach 5.7 comes with an ultra responsive Kashima-coated shock, cause the suspension to move a little more when pedalling than some climbers like. Pivot recommends that Mach 5.7 owners use (or at least try) the RP23 shock’s Propedal function when laying down serious power. We were interested to experience this because previous Pivots, like the Mach 4 and Mach 5, had sufficient anti-squat built into the suspension to never need the Propedal anti-bob function to enhance pedalling efficiency.


Our test bike was fitted with a Fox 32 Float RLC fork and a QR15 axle system, which is pretty important to keep a 150-millimeter-stroke fork with 32-millimeter stanchion tubes carving a tight line through the turns. Kashima coating was conspicuously missing from the Fox fork, and when asked, Pivot officials said that the Mach 5.7 seemed to perform just fine without the slippery coating – especially so after a brief break-in period. The same function that makes dw-link bikes pedal well tends to overdrive the fork, so the fact that the stock Fox fork works well with the Mach 5.7 could be science or serendipity.

Pivot offers five build kits for the Mach 5.7. Our test bike was appointed with the Shimano XTR ensemble highlighted by a 38/26 two-by-ten crankset, hard-stopping Trail brakes with ICE semi-metallic brake pads, and ICE 150-millimeter rotors. Wheels were DT Swiss Tricon 1550 wheels, while tires were a trail-blend of a Kenda Nevegal up front and a Slant Six in the rear (both 2.35-inch). Cockpit items were refreshingly different, with a Syntace P6 carbon seatpost topped by a Pivot signature WTB Vigo Team saddle, and a 90-millimeter Syntace F109 stem clamping Pivot’s 700-millimeter Phoenix carbon riser handlebar. If you haven’t deduced it by now, our Mach 5.7 was outfitted on the trail rider’s side of the mountain bike meter.


We tested the Mach 5.7 on a wide range of Southern California terrain from fast-paced mountain singletrack, to motorcycle routes in the high-desert, and suspension-eating technical boulders and slick-rock in the coastal ranges. Conditions were mostly dry with a couple of lucky super-tack days fed by monsoon rains.


Shock setup: Successful suspension setup is the key to all long-travel trail bikes, and the process is made easy with Pivot’s shock-mounted sag meter. The Mach 5.7 requires a bit more negative travel than most, about 30-percent sag, so use the tool to get it right. Turn off the Propedal function, gently climb aboard, set the spring pressure so that the O-ring lines up with the red line on the plastic indicator and you’ll be good to go. We used the center Propedal option with five clicks out from full slow for rebound.


Fork setup: Up front, we found that 30-percent sag with 3 to 4 clicks of low-speed compression balanced well with the shock. The Fox Fit damping system has an anti-bottom-out feature, so don’t expect the O-ring on the stanchion to run to the end of the fork travel unless you pound something hard enough to bend a rim. Rebound was set 4 clicks out and all seemed well and good.

Pedalling: Rolling out on the Mach 5.7 feels like a different animal than its predecessor. Where the original felt like a long-travel XC ride, the Mach 5.7’s 67-degree head angle steers with more purpose and its suspension feels deeper and more responsive. The sensation leaves the legs wondering if the Mach 5.7 will be a disappointment when powering on the flats or when the climbs begin. Not to worry though, because the new machine accelerates quite well with the shock wide open and nearly matches the original with the assistance of the Propedal lever.

Climbing: Where the Mach 5.7 shines is pedalling up and over rough terrain, where the suspension keeps the bike moving forward noticeably better. The recurved shock rate seems more responsive to terrain under pedalling tension and manages this without stealing leg power. Using Propedal produces a correspondingly rougher ride that feels easier under power, but if you are willing to accept a small amount of pedal-bob, the ‘5.7 will roll smoothly, faster and more efficiently up rooted trails or stepped, slick-rock type climbs with the shock wide open. That said; the advantage of Propedal-assist is more than bob-free pedalling. The Mach 5.7’s rear suspension rides higher when the shock is firmed up which makes the head angle a degree or so steeper. The two actions combine to make the Pivot feel a lot fresher to the legs, especially when ascents last longer than free will. We were not ashamed to reach for the blue lever.


Turning: Surprisingly, the Mach 5.7 corners like it is on rails. There is a beautiful balance that can be felt when the ground is rough and cornering forces are high that makes a ‘5.7 rider want to push harder with each successive turn. The head angle is not so slack that the bike has to be pushed around corners with the outside handlebar. Rather, the 5.7’s steering feels like an integrated part of its handling package – light at the bars with just the right amount of turn-in to encourage a confident flow. We attribute the Pivot’s new found cornering abilities to its lower bottom bracket, modern steering geometry and a better-balance between the shock and fork action. The limiting factor for hard cornering was the rear tire, which turned this phase of testing into a driftathon. Standard fare for the Mach 5.7 is Kenda Nevegals on both ends. The Slant Six rear tire that the factory set us up with accelerates well and rolls fast, but it steals fun from the downhills and is too easy to lock up under braking.

Technical descending: Get ready for some high speed fun when you turn the Mach 5.7 loose on a descent. With sharp, Super D acceleration on tap for rolling climbs and corner exits, and its point-and-shoot turning skills, the Mach 5.7 gets going in a hurry when it catches the scent of gravity. With its Shimano ICE Trail brakes, the choice to pick through the boulders or send it over the top can be made with nanosecond precision and its smooth, balanced suspension action can cover a multitude of errors. Where the original Mach 5 felt like it had a bit less than five inches of wheel travel when pressed, the new ‘5.7 feels a bit better than its posted numbers, especially under braking and when landing flat.


Jumps: On the subject of flying, there is a slight lift in the rear end when popping short, steep ramps, which is typical of trail bikes and short-chainstay all-mountain designs, but a little pull on the handlebar corrects it and from that point, the Mach 5.7 rider will start racking up frequent flier miles. Unless you ask for a tail whip, the ‘5.7 stays on line after the wheels leave the ground and when it returns, the bike is business as usual.

Shimano’s latest XTR two-by-ten transmission is impressive. Shifting feels spot on with every click and we never lost a chain, even when we were pounding slick rock descents spun out in the 38/11 top gear. For those who shift in the push-push (SRAM) mode, Shimano’s dual-action trigger lever feels cramped and slightly out of position regardless of how the shifters are angled. In its intended thumb-and-forefinger mode, however, the latest RapidFire ergonomics feel just right.

We feel that the now-standard 40/28 (SRAM 39/26) double-chainring gearing is too tall for trail work unless your legs are race ready. Shimano’s lower-geared, 38/26 chainrings are a step in the right direction, but unless we hit the steeps when we felt fresh, the tallish low gear often robbed the opportunity to showcase the Mach 5.7’s tractability when the trail got nasty for a lengthily pitch. On the occasion when we did top uber-technical climbs with fresh legs, we left defeated riders open-mouthed on the sideline. Insist on a two-by crankset, but consider 38 by 24 or a 36 by 24-tooth gearing to maximize the Pivot’s performance.

Missing conspicuously from the Pivot Mac 5.7 was a remote-adjust seatpost. The hose guides are on the frame, but the bike did not have the one item that almost every '5.7 rider needs to maximize this stealth shredder's fun factor. As mentioned, we also pondered Pivot's decision to fit a nearly bald Kenda Slant Six tire to such a technically capable trailbike. Order yours with real rubber and shred happily unto the world.


Pinkbike's take:

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View all the options for the mach 5.7 on the Pivot website and check out the new carbon fiber Mach 5.7 due to arrive in late 2011.