Bike Test: Pivot Mach 429SL

The Mach 429SL is a big update on Pivot’s heralded 29er full-suspension platform. The new 429 comes to the table boasting improved carbon manufacturing that shaves a claimed half-pound from the previous generation without compromising stiffness or suspension performance. Pivot prides itself on building bikes that ride well rather than ones that simply meet the numbers set forth by an engineer’s spreadsheet for target weight and stiffness measurements. Each one of Pivot’s new bikes is tested extensively on the desert trails around Tempe, Arizona, where the brand’s headquarters lie, and that’s been a huge part of the brand’s success. When Pivot founder Chris Cocalis invited us to the Tempe facility for a few days of shredding trails and promised to let us leave with the new 429SL for a long-term test, we put the lights of Los Angeles in the rear-view mirror and headed for the desert.

 WHO IS IT MADE FOR?

This bike is tough to classify, because it could be raced under cross-country gram counters or enduro specialists. It is a 29er cross-country bike that doesn’t want to be pigeonholed into a single discipline. Instead, the 429 strives to climb quickly and efficiently, and still deliver stiffness and suspension performance on the descents that will keep trail riders smiling. This is a lightweight, short-travel bike, but it’s one we also felt comfortable taking on our most difficult and technical test trails.

WHAT IS IT MADE FROM?

The Mach 429 is built entirely from carbon with a relatively short chainstay, roomy top tube, low bottom bracket and incredibly stiff chassis that bring the bike alive. It sports 4 inches (100 millimeters) of rear-wheel travel, a tapered head tube designed for an internal headset, a 12- x 142-millimeter rear axle, and is built around 29-inch wheels with an option for a 100- or 120-millimeter-travel fork platform. The frame also features cable routing for Shimano Di2 routing, or full internal routing for a mechanical drivetrain and dropper seatpost with just a quick swap of the included cable guides. The bike is also available with over 10 different build kits to accommodate nearly any budget.

WHICH COMPONENTS STAND OUT?

The details in the design are the standout here. Put a Pivot 429 frame on the scale next to a competitor’s 4-inch 29er and you might be a little disappointed, but that’s only because Pivot has done its homework and has built this frame around the latest and greatest hardware out there. The frame uses a Press-Fit bottom bracket, internal headset, and a different carbon layup for each and every size frame that comes out of the mold. Because of this, there is more material in a Pivot frame. Bottom line, a Pivot 429 frame is not the lightest out there, but with that said, the complete bike nets a competitively lightweight and impressively stiff package that only fellow Pivot riders will appreciate. The Maxxis Ardent Race tire setup provides plenty of traction in a lightweight and fast-rolling package. The high-volume, 2.2-inch-wide casing also provides a nice and supple ride.

 HOW DOES IT PERFORM?

Setting sag: Pivot makes the initial setup very easy with its included sag guide. The plastic shock measuring tool zip-ties to the air sleeve, providing a perfect guideline for recommended sag, including different recommendations for racing and trail riding. We set the bike to the Trail mode for the duration of the testing, at about 25 percent. We then matched the fork to the same sag and hit the trails.

Moving out: Before you even throw a leg over the Mach 429, you’ll think the size you’re used to riding is a size small. That’s thanks to the designers at Pivot building an impressively sloping top tube that provides loads of stand-over height. Our large test bike fit true to size for the important measurements, like effective top tube length and seat tube length, so we just sat back and appreciated the extra clearance. Pivot even found a way to fit a full-sized water bottle into the frame, although you’ll need to flip the shock so the CTD lever faces up to get the clearance.

Pedaling: Pivot’s interpretation of the dw-link suspension design is a little plusher than others we’ve ridden, but it still offers the anti-squat characteristics we’ve come to know and love with these bikes when the pedals are pushed. Out of the gate, the Mach 429SL feels plenty snappy and pedals bob-free in the Trail mode on the Fox CTD shock. In fact, we rarely found the need to use Climb on the shock, simply because the anti-squat does most of the pedal-bob resistance for you.

Climbing: The anti-squat characteristics couple perfectly with the short-travel frame to provide a bike that loves to dig in and claw its way up technical terrain. The 29er hoops are surprisingly lightweight, thanks to carbon rims and a smart and racy tire setup, which makes this bike want to ascend that much more. We only felt the need to put the shock or fork in the “Climb” mode on fire roads or paved sections, simply because the bike felt so efficient on any singletrack in the Trail or Descend modes.

Cornering: The Mach 429SL sports a relatively short wheelbase and chainstay length, matched with a racy 69-degree head angle. This makes the bike feel lively and quick on the trail, just like a race bike should. While many 29ers feel cumbersome in tight corners and switchbacks, this bike proved its mettle by making it through our tightest test tracks.

Descending: This is a cross-country bike, and it should be treated as such. It ascends like a banshee, and we wouldn’t balk at giving it a good review even if it made our best test riders pucker on the descents. We’re happy to say, however, that this wasn’t the case.

After a few rides on the 429SL, we found a rhythm that had us shredding descents as if we were riding a bike with much more travel. This bike won’t do the work for you, but the frame stiffness and excellent suspension allow for some serious speed on even the rockiest of descents. This is not an “enduro” bike, although several of Pivot’s team members have chosen this as their weapon of choice for the most pedal-intensive enduro stages. The 429SL strikes a nice balance between lightweight pedaling efficiency, serious stiffness and suspension performance.

Braking: Pivot’s take on the dw-link suspension design does a great job of isolating both pedaling and braking inputs from the suspension. As a result, this bike feels active, whether the rider is pedaling through a tough section or hard on the brakes preparing for a corner.

TRICKS, UPGRADES OR TIPS?

On our first few long rides, the seatpost slid down, forcing us to stop and break out the multi-tool to raise the post again. We reinstalled the post with some “friction paste,” a sort of assembly paste that keeps this from happening, and we never had the problem again. Pivot recommends using Motorex’s Assembly Lube to solve this small issue.

 BUYING ADVICE

This bike is light enough to dice it up on a World Cup cross-country course and designed well enough to hang with bikes with much more travel. It is impressively stiff on the trail and puts every bit of power to the wheels. It’s a cross-country bike, but we’d be hard-pressed to find one with more range than this. The 429SL delivers excellent suspension performance and a dialed geometry that’s rivaled by few. The price tag will be a barrier to entry for some, but Pivot offers several build packages with the same excellent frame performance at a greatly reduced price. The Pivot Mach 429 is a race-ready cross-country bike with some serious trailbike chops.

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