Has it really been six years since we’ve tested a
Pivot Mach 4? Hey, it’s not our fault. Pivot springs
so many innovative bikes on us—including the
do-it-all Mach 5.7 trailbike, the long-travel Firebird, and the
featherweight, carbon-framed Mach 429er—that it is easy to
forget that the Pivot revolution started with the Mach 4.
WHO IT IS MADE FOR?
This isn’t an easy question to answer, because the Mach 4 is available in seven build kits, from the $6399 Shimano
XTR to the $3999 Shimano XT/SLX build tested here. The
further you move toward the high end, the more viable the
Mach 4 is for serious cross-country racing, mostly because of
the weight savings. Our Mach 4 was designed more for the
trail rider, albeit the trail rider who likes to push the pace.
WHAT IS IT MADE FROM?
The Mach 4 relies on oversized, thin-walled, hydro-formed
alluminum tubes; hollow, 3D forgings; and oversized pivots.
The frame is available in six sizes, and the frame tubes are
tuned for the specific sizes. The small isn’t harsh, and the
extra large isn’t a noodle. Pivot uses a zero-stack headset
system that allows the front of the frame to sit about 1/2-inch
lower than normal. The zero stack differs from integrated
headsets in that the bearings still ride inside a machined cup
that is pressed into the frame. You get a PressFit 92-millimeter-wide bottom bracket, direct-mount front derailleur, and a
dw-link rear suspension with a high-modulus carbon rocker.
WHICH COMPONENTS STAND OUT?
The Mach 4 XT/SLX component mix is special. It’s like
Pivot’s engineers spec’ed a custom bike for a favorite client,
but they are letting you ride it. How so? The non-matching
Magura MT2 and MT4 (rear) brakes are something special
that Magura does for Pivot. Pivot also specs non-matching
Kenda Nevegal and Slant Six (rear) tires. The Mach 4 has a longer-travel Fox fork and wide handlebars with lock-on
grips. It has a 2x10 drivetrain and a Shadow Plus rear derailleur. The shock is Kashima-coated. It comes with a WTB
saddle, a wrapped chainstay and color-matched hardware. These aren’t choices designed to optimize profits; they
are designed to optimize performance.
HOW DOES IT PERFORM?
The setup: Pivot takes most of the guesswork out of setting the rear
suspension by giving you a sag measurement tool. Start with Pivot’s
recommended setting and you probably won’t budge from it. The CTD
(Climb, Trail or Descend damping modes) shock has the Trail Tune option, giving you three fine-tuning options in Trail mode. The fork also
offers the CTD feature.
On the trail: The wide bars, 90-millimeter stem, super-supportive saddle and just-the-right-length top tube put the rider in a trail riding position that feels as comfortable for a one-hour jam fest as an
epic ride. The tight frame and stays do not contact the rider’s
legs, and the same goes for the cable and hose routing.
Acceleration: The 2x10 drivetrain was first invented
when 26-inch wheels ruled the trail. Although there are
compromises with larger wheels and a 2x10 drivetrain, the
combination feels perfect in this application. The lowest gear
is almost 12 percent lower than it would be on the same bike
with 29er wheels, and anyone can feel that difference from a stop. Clicking through the gears while moving up to speed
feels tight and smooth. Interrupted cable housing also adds to
the crisp shifting performance.
Cornering: The longer-travel fork slackens the head tube
angle, making this Mach 4 far more trail-rider-friendly than
the steeper head tube angle you’d get using a 3.9-inch-travel
fork. This, along with the sticky Nevegal tire, allows the rider
to relax and flow the corners without stressing about obstacles (just hit them) or the trail surface (just roll it).
Climbing: While the dw-link rear suspension can handle
out-of-the-saddle efforts, the Mach 4 will reward the rider for
staying seated, selecting the Trail (or Climb) shock mode, and
allowing the 26er-optimized 2x10 drivetrain to work its magic.
Crewers were shocked to learn of the bike’s 28-pound weight.
Not that 28 pounds is horrible; it’s just that the bike feels much
lighter. The best technique for climbing on the Mach 4 is to
maintain a light touch on the grips and to keep your weight
forward and your torso low on steeper ascents. Otherwise, the
bars will tend to scissor as the front end becomes light.
Descending: Maybe we should eliminate spec charts from
our bike tests. Why? Numbers lie. We already told you the
Mach 4 feels lighter than its actual weight, and now we are going to tell you that it has descending chops way beyond
what you’d expect from a 3.9-inch-travel, 26-inch-wheeled
“cross-country” bike. This bike is so much fun on downhill
trails. Maybe in a side-by-side comparison the Mach 5.7
would provide a deeper feel on G-outs and the Mach 429
would roll smoother in craggy rock sections, but the Mach
4 delivers a feeling of complete control and confidence.
It may only have 3.9 inches of travel, but it is a great 3.9
Braking: Pivot continues to deliver with this bike’s braking
spec. The mix-and-match Magura MT2 and MT4 brakes are
slightly heavier than the MT8 brakes because they undergo
less machining to save weight. The additional material results
in a stiffer caliper that provides increased braking power. You
get plenty of stopping power up front and rear-wheel braking that allows for great traction control, even while moving
through and over the rough stuff.
TRICKS, UPGRADES OR TIPS?
This bike loves to be pumped along the trail (unweighting the bike on the face of bumps and weighting the bike
on the backside) because the dw-link rear suspension has a
firm mid-stroke. Whereas pumping will cause you to blow
through the travel on other designs, the mid-stroke resistance makes pumping a blast on the Mach 4. You can also
use this trait to slightly preload the suspension for hopping
The Pivot Mach 4 doesn’t bring anything new to the
table, and maybe that’s why we like it so much. Pivot has
refined their initial offering, allowing riders to experience
what a truly pedigreed mountain bike feels like. This bike
is the real deal. It is a mountain bike, first and foremost.
If you have already bought into larger-diameter wheels
(29 or 27.5), carbon fiber frames or 5-plus inches of travel,
we wouldn’t expect you to add the Mach 4 to your plan-to-buy list. This bike makes the most sense for a rider who
wants to replace his five-year-old production bike. If you
wanted to buy this bike five years ago but the price stopped
you, well, friend, it’s time.