Pivot Mach 4 Carbon first ride review

Smaller wheels deliver more XC speed

The Mach 4 is hardly a new name for Arizona-based Pivot Cycles. The XC race rig was one of their first bikes and has been in the line-up ever since, going through myriad updates. The latest is this 27.5in wheel, 115mm rear travel XC race bike with trail bike versatility. 

A Fox Float Factory DPS shock damps the 115mm of dw-link travel
A Fox Float Factory DPS shock damps the 115mm of dw-link travel

Pivot Mach 4 highlights

  • Full carbon frame 
  • 115mm travel dw-link suspension with race and trail tuning (XS size has 100mm travel)
  • 27.5in wheels
  • Fits tires up to 2.6in
  • Available in either trail-oriented or XC racing-focused complete bike builds
  • XS, S, M, L & L(long) sizing, with X-Small featuring super low stand-over clearance
  • Claimed frame weight from 5.1lb/2.3kg 

Pivot Mach 4 build details

The Mach 4 in for test features the trail-focused Team XTR 1x build and as you might expect, there's very little room for want. The carbon frame is loaded with a Fox 34 Factory with 130mm of travel. Rear end action is handled by a Fox Float Factory DPS shock yielding 115mm.

If I had my way every XC bike would have a Fox 34 on the front end
If I had my way every XC bike would have a Fox 34 on the front end

The 27.5in wheels are gorgeous DT Swiss XMC 1200 carbon hoops that I have high expectations for. The same can be said for the Shimano XTR 11-speed (XT cassette 11-46) with Race Face Next SL cranks (30T) and Shimano XTR Trail brakes.

Maxxis Ardent Race 2.35in tires are on board, although I will be testing other rubber since the Mach 4 can swallow 2.6in widths. I was also pleased to see a Fox Transfer dropper post fitted. 

Pivot Mach 4 first ride impressions

Spinning up the trail on the Mach 4, for whatever reason I kept reminiscing back to when I was much more XC obsessed. Back then it wasn't really a conscious decision, XC was all there was, so it was the only riding I knew. What I did know was I wanted to go fast and ride loose. It was too bad the bikes sort of sucked. 

But now there are bikes like Pivot's Mach 4 Carbon. 

Based on the first ride, speed shouldn't be much of an issue for the newest Mach 4
Based on the first ride, speed shouldn't be much of an issue for the newest Mach 4

Granted, it's rare nowadays to find an short-travel XC bike rolling on 27.5-inch wheels, but as my ride progressed I began to wrap my head around why this bike had the smaller wheels.

Here's why. When it comes to cross country racing and riding, the old adage is everything is won or lost on the climbs. That's true, but now that almost every bike company has a featherweight XC rig, it's sort of equal. The other spot to grab a lot of time is in and out of the corners. 29in wheels, due to sheer size, are slower to gain speed. That means a 27.5in bike can get back up to race pace quicker in the tight stuff. Less gyroscopic effect also means it's a bit more playful.

I was impressed with the sheer acceleration of the Mach 4. I did a decent climb the day before so I assumed my legs would be a bit hollow, but with every flick of the cranks, the whooosh of the air rapidly got louder in my ears. With the stiff carbon frame and wheels, and responsive rear suspension, getting up to speed felt effortless and really, really fun.

With the 27.5in wheels it felt like I could just live in the high end of the cassette, especially since the bike I have has a paltry 30T ring. This is one thing I might change in favor of a 34t or 36t chainring depending on the situation. 

27.5 x 2.35in Ardent Race tires are nod to fun over all out speed
27.5 x 2.35in Ardent Race tires are nod to fun over all out speed

On the uphills, I initially left the Fox Float rear shock open. There was a tiny bit of movement so I nudged the lever over to the middle setting which tamed the movement even more. Being that the dw-link rear end is super efficient and the trails I ride are loose and techy, the firmest shock setting is of little to no use for me. 

With gravity's assist, the Mach 4 surprised me by feeling a bit deeper than its 115mm travel. Sure, that can be taken as cliche, but I think it's more a testament to a well-sorted rear suspension. The front end complimented the back. I'm a huge fan of the Fox 34 and its 130mm of travel didn't disappoint here. 

I did notice the smaller wheels getting hung up a bit more through chunky sections and the Ardent tire's knobs getting a bit overwhelmed in some corners, especially on the front. I'm very interested in seeing what happens when I throw on larger, wider tires.  

Pivot's house brand Phoenix provides the 35mm clamp bar and stem
Pivot's house brand Phoenix provides the 35mm clamp bar and stem

Pivot Mach 4 Carbon pricing and availability

The Team XTR 1x retails at $7,799 (UK and Australian pricing TBD). Pivot offers an incredible 14 different build kits divvied up between XC Race builds featuring a 100mm travel fork and narrower tires and the more trail-oriented builds with a 130mm fork and wider tires.
The base level starts at $4,599 (UK and Australian pricing TBD) for a Race XT 1x build and works up from there. Have your own parts? Frame pricing is $2,899 (UK and Australian pricing TBD).
Russell Eich

Tech Writer, US
Russell fell head over heels in love with bikes in the '90s, and has been involved in the bike industry ever since. Between wrenching in bike shops, guiding professionally, and writing about bikes, Russell has honed an appreciation for what works, gained knowledge of what doesn't, and can barely contain his enthusiasm for what comes next. His two-wheeled passion continues in the Rocky Mountains high above Boulder, Colorado.
  • Discipline: Mountain, road, cyclocross
  • Preferred Terrain: High altitudes, forgotten singletracks, bike parks, roads without cars
  • Current Bikes: Custom Meriwether steel hardtail, Specialized S-Works Enduro 29, Kona Jake the Snake, Trek 69er, and a bunch more
  • Dream Bike: Yeti SB5c, Intense Tracer 275C, Black Cat custom road
  • Beer of Choice: Gin + Tonic
  • Location: Rollinsville, CO, USA

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