Bible Review: Pivot Mach 5.5 Pro XT/XTR 1X

Nimble handling, stock 2.6-inch tires and a vastly more supple suspension feel make this 27.5er shine on technical terrain

The Fox Float Factory DPS EVOL is a good boinger in its own right, but compared to the burly Fox 36 on the party end of Pivot's newest Mach 5.5, it looks undergunned. But once we stopped looking and started riding, we immediately noticed a whole new level of rear-suspension sensitivity and suppleness.

There's only 140 millimeters of travel out back, but you wouldn't know it. The Mach 5.5 is active and linear-feeling, and when combined with 2.6-inch Maxxis Rekon and Minion tires, is deceptively deep-feeling. This makes the bike excel at pedaling through undulating techy bits, where it seems to make chunky rocks and root balls disappear underneath it without any noticeable pedal feedback. On climbs, however, that extra-active, linear suspension could be an energy drain--an unexpected attribute coming from Pivot, whose bikes are normally rocket ships uphill. It sits up and becomes continually more efficient as you start laying the power on, though. It's laggy and slow if you're laggy and slow, but picks up when you do, which is great, except that it sort of feels as though it's forcing you to go hard instead of inspiring you to. Of course, the shock has a 'Medium' setting, which makes the bike more efficient.

Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image
Gallery Image

Testers described the Pivot's descending ability as, "Feels best at speed," and "Lively and maneuverable at speed." Compared to the Ibis Mojo HD4, which also uses dw-link suspension, comes with a 160-millimeter-travel fork and 2.6-inch rubber, the Mach 5.5 feels less planted. That makes sense considering the HD4 has a longer wheelbase and much slacker head angle. The Pivot's 66.5-degree stance puts it more in the aggressive trail game, whereas the Ibis is targeted at the enduro scene. Despite this, the Ibis is a more efficient pedaler. The Mach 5.5, on the other hand, dances on the trail with an exceedingly poppy, playful attitude that begs to be manualed, slid around corners and pointed toward trailside extra-credit treats.

Pivot gave the Mach 5.5 enough reach to spec 45- and 55-millimeter stems (depending on size), but should've gone with a bar wider than 760 millimeters--trimming bars is free, but making them wider isn't. Pivot is positioned as a premier brand, and its spec and pricing reflects this. Cost of entry for a complete Mach 5.5 goes for $4,900 and if you want a SRAM Eagle drivetrain, you're in for $7,100. What's nice about Pivot, though, is there's no skimping on important stuff like suspension, tires or wheels.


Visit the 2018 Bible for more reviews


Q&A with Chris Cocalis, Pivot Cycles president and CEO

What's the reasoning behind designing the Mach 5.5 with 140 millimeters of rear wheel travel, and 160 millimeters up front? Although this isn't at all unheard of, it's more common to see bikes with more even gravel numbers. 

The Mach 5.5 is tough to put in a category, with uneven suspension and almost-plus tires. That didn’t bother Satchel Cronk though.

With the dw-link design, the rear generally feels like it has more travel. As we went through prototyping, we started testing with 160-millimeter forks to test in places that were more at the limit of the bike's intention. We liked the front to rear balance it provided both in these conditions and in less-aggressive terrain. Overall, we felt that the 160-millimeter travel fork gave the bike the best front to rear balance.  The new Fox forks have really good mid-stroke support, so adding a bit of travel up front is never a bad thing when you can maintain the balance and the intended overall feel of the bike. It opens up the capabilities of the Mach 5.5 a bit more.

What's your take on the 2.6-inch tire? Does it count as 'plus?' What advantages and disadvantages will riders experience in your opinion?

We like the 2.6-inch tire size because it offers a high level of confidence and traction. 27.5 x 2.6-inch is nearly identical to a standard 27.5-inch Wide Trail tire because its diameter is in line with the normal range of 27.5-inch tires. Widthwise, they have a bit more volume but oftentimes the knob width on a 2.4- or 2.5-inch WT tire can actually put those tires at a slightly wider overall measurement. The 2.6-inch tire strikes a nice balance because it can be ridden aggressively but still offers nice flotation and is fast rolling compared to more aggressive enduro-specific tire designs. It’s a nice match to the 35-millimeter rims on the Mach 5.5. 'Plus' tires are larger in overall diameter and volume. The actual overall tire size difference and volume is much more than the 2.6-inch and 2.8-inch logos would suggest. With the 'plus' tires you get a pretty significant bottom bracket height change compared to the 2.6-inch tires. From a frame builder's perspective, designing a bike for 'plus' size with their larger size and volume requires a different bike design and fits better into the mix with a bike that can handle 29er and 27.5+ wheels. With 'plus' tires, the traction is unreal and the fun factor overall is really high. The current downside is that more tire volume either equals more weight or less durability so the liveliest tires cannot be ridden at a pro-level DH or enduro race pace without pinching or cutting and the most durable tires are pretty heavy. I love the 'plus' size in slow technical terrain and loose technical climbing because it really has incredible traction everywhere. The 2.6-inch gives you some of that same feeling but the weights can be kept lower. Also, with the 2.6-inch size, because the diameter is very similar to a standard 27.5-inch tire, the rider can choose more aggressive tires in the 2.3- to 2.5-inch range as long as they are approved for 35-millimeter-wide rims.

What type of rider is the Mach 5.5 designed for?

Pivot has built a reputation around bikes that climb just as well as they descend. Lacy Kemp sees if that holds true with the Mach 5.5.

The all-round mountain biker/trail rider. The Mach 5.5 can handle anything just short of a full-on bike park but it also pedals efficiently enough that the occasional 24-hour race or endurance event is not outside of its capabilities.

Why no Super Boost Plus 157? 

We use Super Boost Plus where it’s needed. With the Mach 5.5, we were able to achieve all the tire clearance, crank/chainring clearance, travel and frame stiffness that we needed with Boost. The fact that this is not a 27.5+ or 29er bike makes that much more achievable.

What's better, the Mach 5.5 or the Switchblade? 

They are both the best in their respective categories. The Mach 5.5 is an incredible all-round trail bike.  The Mach 5.5 strikes a nice balance between pedaling efficiency and downhill capability and it’s a bike that can do it all. The Switchblade is an extremely versatile 29er/27.5+ bike and even though the two models look very similar on paper, the Switchblade feels and behaves like a bigger-travel enduro bike. At demo events, we get a pretty even split of riders telling us which one they will want to go with and the sales reflect that as well. With the tire choices alone, there is a big difference in how the bikes ride with the Mach 5.5’s 2.6-inch tires vs the Switchblade’s 29 x 2.4/2.5-inch or the 27.5 x 2.8-inch tires. It’s nice to be able to give riders options.

There's really no 'budget' spec available. Complete bikes start at just under $5,000, whereas it's not uncommon to see other full-carbon bikes available at a lower cost of entry. Why is this? 

It might not be cheap, but from carbon bar to Shimano drivetrain, you are getting a bike built for performance.

We don’t really do 'budget.'  The Mach 5.5 starts at $4,900 and it’s a build that anyone at Pivot would be proud to own. This is a high-end bicycle and we are happy to keep it that way. We want every Pivot rider to be able to buy a Pivot and own it for the duration and be able to ride it at the same level as our $6,000+ builds without issues or compromise.