Pivot Cycles Goes Big With 170/162mm Travel Firebird 29er

by Wil Barrett 0

Officially unveiled as of today, Pivot Cycles has just taken the wrappers off this brand spanking new long-travel 29er called the Firebird 29.

Joining the existing Firebird 27.5, the 29er version takes on many of the same ingredients including a gargantuan carbon fibre frameset that is bold, burly and stiff. Designed for enduro racing and park riding, the Firebird 29 features a 170mm travel fork up front, and no fewer than 162 millimeters of travel out back via the dw_link suspension design.

Like the Switchblade and Trail 429, the Firebird 29 is compatible with both 29in wheels and 27.5+ wheels, and it features adjustable geometry that allows for both Low and High ride-height settings. To provide huge tyre clearance while accommodating the 162mm rear travel, Pivot has elected to use a wider 157x12mm rear hub and a 6mm offset drivetrain called ‘Super Boost Plus’. This allows the chainstay length to be built super short at 431mm, providing the Firebird 29 with plenty of agility for a bike equipped with big wheels and big suspension.

pivot firebird 29
Pivot’s new Firebird is a new 162mm travel 29er enduro/park bike.

Pivot Firebird 29 Features

  • Long travel 29er enduro/park bike
  • Compatible with 29in or 27.5+ wheels
  • Max tyre clearance: 29×2.6in, 27.5×2.8in
  • Full carbon fibre frame w/alloy linkages
  • dw_link suspension design
  • 162mm rear travel
  • 170-180mm fork travel
  • 65 head angle
  • 74.5 seat angle
  • Reach: 428mm (Small), 455mm (Medium), 475mm (Large), 498mm (X-Large)
  • Chainstay length: 431mm
  • High/Low geometry settings
  • 1x specific frame design
  • PF92 bottom bracket
  • Super Boost Plus spacing w/157x12mm rear hub
  • Claimed frame weight: 3.2kg (Medium size w/shock)
  • Complete bike RRP: £5,100 – £8,500
pivot firebird 29 fox 36
The carbon fibre frame is built with huge box-section tubes and a robust 1.5in diameter headtube. Photo: Jens Staudt.

Big Bird

With its huge Fox 36 fork, piggyback shock and 2.5in Wide Trail tyres, the Firebird 29 has got a real monster truck vibe about it. The low-slung frame is made from carbon fibre (there are no plans for alloy frames at this point in time) with an enormous downtube and a stout-looking double wishbone swingarm. There’s a straight 1.5in headtube that’s Angleset compatible, and the frame is even rated for use with a dual crown downhill fork. Yikes!

Just like the new Trail 429, the Firebird 29 is 1x specific. That allows the lower linkage of the dw_link suspension platform to be built much wider, resulting in higher strength and stiffness values through the rear end. All four pivot points roll on the same large diameter Enduro MAX bearings.

pivot firebird 29 fox 36
The dw_link suspension design features two small alloy links that connect the carbons swingarm to the mainframe. Photo: Jens Staudt.

A familiar feature is the huge 92mm wide bottom bracket shell, which eschews any additional bonded alloy threads in favour of a smooth, hollow carbon fibre tube. Much like the headset, the PF92 BB is designed to accommodate press-fit cups. Even though Pivot’s frames are manufactured in the same factory as a few other high-end mountain bike brands, we’re told that the tolerances that they specify (like the inner diameter of the BB shell) are much higher – to the point where Cocalis is known at the factory to be a bit of a pain in the arse. For him, it’s pretty straightforward though: tighter tolerances equals a tighter fit. And according to Pivot, it has never had an issue with creaky BBs in the past.

Though the BB is encircled by ISCG 05 tabs, Pivot has developed its own minimalist upper chainguide, which comes standard on the complete bikes.

To get all the rear travel into the frame along with a low standover height and a short seat tube though, Pivot had to sacrifice water bottle mounts inside the mainframe. And unlike the Firebird 27.5 and other models such as the Mach 5.5 and Switchblade, Pivot has omitted any Di2 or Fox Live Valve compatibility, since it sees a fairly specific rider in mind for this bike.

pivot firebird 29 fox 36
There’s internal cable rouging throughout and thick rubber armour in the key strike zones. Photo: Jens Staudt.

Big Suspension, Big Rubber

Rear travel on the Firebird 29 sits at a very specific 162mm. Controlling that travel is a Fox Float X2 shock and Dave Weagle’s dual-linkage suspension platform. In order to accommodate the big 29in rear wheel, the upper rocker link sits forward of the seat tube, with a mini-clevis sandwiched in between the rocker link and the rear shock eyelet. This compact clevis (or shock yoke as it’s sometimes referred to) is lighter and stiffer, and it produces a steeper leverage curve with a little more progression.

pivot firebird 29 fox 36 fox 36 fox float x2
Adjustable geometry allows for Low and High pre-set positions. Photo: Jens Staudt.

Up front is a 170mm travel fork, though you can go up to 180mm if you like. Unlike Pivot’s shorter-travel 29ers though, the Firebird 29 is running a 44mm fork offset, instead of the usual 51mm. In testing on the Firebird 29, Cocalis found that the shorter fork offset provided a more aggressive turn-in for high-speed cornering, along with better front wheel bite on steeper descents. In comparison, the 51mm fork offset delivered a more natural and neutral-feeling front end on less steep terrain. Given that the big-travel Firebird is targeted towards more aggressive, and more experienced riders though, the shorter 44mm offset became the preferable option.

pivot firebird 29 fox 36
Pivot is spec’ing the Firebird with a burly Fox 36 fork up front with 170mm of travel. Photo: Jens Staudt.

Super Boost Plus

This being a bike of 2018, the Firebird 29 is cleared for use with up to a 2.6in wide tyre. It’s also 27.5+ compatible, with room to fit a 27.5×2.8in tyre in the rear. That’s an impressive amount of clearance for such a big travel bike. But then you see the geometry chart and the quoted chainstay length. 431mm. That is insanely short for a bike of this stature, and it comes back to Cocalis’ original requirement for the Firebird 29 to be something that was still nimble and playful.

pivot firebird 29 super boost plus
157x12mm rear hub spacing. Photo: Jens Staudt.

In order to achieve such a short back end while producing 162mm of travel with clearance for 2.8in tyres, Pivot has elected to run a 157x12mm rear hub. Referred to as ‘Super Boost Plus’ spacing (tongue firmly in cheek), this rear hub width is the same as what you’ll find on a regular downhill bike. The only difference is that the hub flange is pushed out a bit wider on the disc-side, in order to increase spoke triangulation to produce a stiffer wheel. Functionally there’s no other difference with regular 157x12mm rear hubs – the disc rotor and cassette sit in exactly the same position.

The real benefit of Super Boost Plus is the increased chainring clearance though, which rather than being pushed out by 3mm (à la regular Boost), is pushed out 6mm. Once you’ve got that extra room to play with, then you can start slamming the rear wheel in right up against the BB shell. To get this 6mm offset, the chainring is simply flipped around, so the cranks and BB are no different to any other Boost or non-Boost setup. Crucially, this keeps Q-factor the same as a regular Boost bike.

pivot firebird 29
Huge tyre clearance in the back. Photo: Jens Staudt.

Unfortunately for Pivot, the brand copped a lot of flak when it first went Super Boost Plus on the Switchblade two years ago. There was quite a bit of misinformation being spread amongst the sea of pitchforks, though perhaps the Arizona-based brand is also guilty for not explaining things better. Indeed many consumers were upset by a new standard, even though SBP didn’t actually introduce any new standards – it just developed a better arrangement around existing standards.

What will help tell the SBP story is this bike, which completes Pivot’s 29er trail bike line up. Now we have the Trail 429 (120mm), the Switchblade (135mm) and the Firebird 29 (162mm) all using SBP spacing, and all providing short rear centres with plus-tyre compatibility.

pivot firebird 29
The Super Boost Plus spacing offsets the drivetrain by a full 6mm to run shorter stays. Photo: Jens Staudt.

Reachey McReach Reach

Once known for its use of much sharper angles and short top tube lengths, Pivot Cycles has accelerated into the future with its most recent offerings. Steep and short is out, and ‘shlong’ (Slack & Long) is most definitely in.

And the Firebird 29 is about the shlongest bike that Pivot has ever made. There will be four frame sizes available, with reach starting at at 428mm for the Small, going up to 495mm for the X-Large. According to Pivot, this will cover riders from 5ft4in up to 6ft7in tall.

Key numbers include a 65° head angle, a 74.5° seat angle, and a bottom bracket height of 341mm. These can be steepened by way of an adjustable eccentric pivot at the top of the seatstay and rocker link junction. Or they can be slackened by using a 17mm lower headset cup that extends the effective fork length. Either way, there’s a good deal of adjustment available for fine-tuning the geometry and the riding position whether you’re running 29in or 27.5+ wheels.

Firebird 29er geometry in the ‘Low’ position.
And in the ‘High’ position.

Complete Bikes

Just like Pivot’s other SBP bikes, the Firebird will only be available as a complete bike. At least to begin with anyway.

All bikes will be spec’d with beefy Maxxis Minion tyres (2.5in on the front, and 2.4in on the back), along with rims between 30-34mm wide internally. There are drivetrain options from both Shimano and SRAM, but suspension exclusively comes from Fox, with a 36 fork on the front and either a DPX2 or Float X2 shock on the rear.

pivot firebird 29
Chunky Wide Trail Maxxis tyres feature on each Pivot Firebird model. Photo: Jens Staudt.

The cockpit setup is standardised between all bikes, with an 800mm wide bar paired to a short 45mm stem. Likewise, the PadLoc grips and WTB Hightrail saddle are consistent for each of the six build options, and depending on the frame size you go for, you’ll get a 125-150mm travel dropper post.

pivot firebird 29
800mm wide bars and a stubby 45mm stem come on each frame size. Photo: Jens Staudt.

Firebird 29 Race XT Build

  • Frame // Hollowbox Carbon Fibre, 162mm Travel
  • Fork // Fox 36, Performance Series, GRIP Damper, 170mm Travel
  • Shock // Fox Float DPX2 or Float X2, Performance Series
  • Wheels // Sun Ringle Duroc 29, 30mm Internal Rim Width
  • Tyres // Maxxis Minion DHF EXO 3C MaxxTerra WT 2.5in Front & Minion DHR WT 2.4in Rear
  • Drivetrain // Shimano SLX/XT 1×11
  • Brakes // Shimano SLX M7000
  • Price // £5,350 / £5,450

Firebird 29 Race X01 Build

  • Frame // Hollowbox Carbon Fibre, 162mm Travel
  • Fork // Fox 36, Performance Series, GRIP Damper, 170mm Travel
  • Shock // Fox Float DPX2 or Float X2, Performance Series
  • Wheels // Sun Ringle Duroc 29, 30mm Internal Rim Width
  • Tyres // Maxxis Minion DHF EXO 3C MaxxTerra WT 2.5in Front & Minion DHR WT 2.4in Rear
  • Drivetrain // SRAM GX/X01 Eagle 1×12
  • Brakes // Shimano SLX M7000
  • Price // £5,750 / £5,850

Firebird 29 Pro XT/XTR 1x Build

  • Frame // Hollowbox Carbon Fibre, 162mm Travel
  • Fork // Fox 36, Factory Series, FIT GRIP2 Damper, 170mm Travel
  • Shock // Fox Float DPX2 or Float X2, Performance Series
  • Wheels // DT Swiss M1700, 30mm Internal Rim Width
  • Tyres // Maxxis Minion DHF EXO 3C MaxxTerra WT 2.5in Front & Minion DHR WT 2.4in Rear
  • Drivetrain // Shimano XT/XTR 1×11
  • Brakes // Shimano Deore XT 4-Piston
  • Price // £6,400 / £6500

Firebird 29 Pro X01 Build

  • Frame // Hollowbox Carbon Fibre, 162mm Travel
  • Fork // Fox 36, Factory Series, FIT GRIP2 Damper, 170mm Travel
  • Shock // Fox Float DPX2 or Float X2, Performance Series
  • Wheels // DT Swiss M1700, 30mm Internal Rim Width
  • Tyres // Maxxis Minion DHF EXO 3C MaxxTerra WT 2.5in Front & Minion DHR WT 2.4in Rear
  • Drivetrain // SRAM X01 1×12
  • Brakes // Shimano Deore XT 4-Piston
  • Price // £7,300 / £7,400

Firebird 29 Team XTR 1x Build

  • Frame // Hollowbox Carbon Fibre, 162mm Travel
  • Fork // Fox 36, Factory Series, FIT GRIP2 Damper, 170mm Travel
  • Shock // Fox Float X2, Factory Series
  • Wheels // Reynolds Black Label Enduro 29, 34mm Internal Rim Width
  • Tyres // Maxxis Minion DHF EXO 3C MaxxTerra WT 2.5in Front & Minion DHR WT 2.4in Rear
  • Drivetrain // Shimano XT/XTR 1×11
  • Brakes // Shimano Deore XT 4-Piston
  • Price // £8,000

Firebird 29 Team XX1 Build

  • Frame // Hollowbox Carbon Fibre, 162mm Travel
  • Fork // Fox 36, Factory Series, FIT GRIP2 Damper, 170mm Travel
  • Shock // Fox Float X2, Factory Series
  • Wheels // Reynolds Black Label Enduro 29, 34mm Internal Rim Width
  • Tyres // Maxxis Minion DHF EXO 3C MaxxTerra WT 2.5in Front & Minion DHR WT 2.4in Rear
  • Drivetrain // SRAM XX1 1×12
  • Brakes // SRAM Guide Ultimate
  • Price // £8,900

For more information on how the Firebird 29 rides on the trail, check out my first ride review of the Pivot Firebird 29 Pro X01 here.


Disclosure

Flights and accommodation for this trip were covered by Pivot Cycles.

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