Pivot is a relatively new brand, but its founder Chris Cocalis (who also founded Titus) has been at the top of the mountain bike charts since the dawn of the dual-suspension trailbike. Loyal readers will know that Chris has designed a number of Mountain Bike Action's all-time favorite rides, but the Pivot Firebird, eclipses everything he has made to date. The Firebird is a showcase for Chris' innovation and almost clinical attention to minutia, but there is a degree of maturity to its design-a touch of restraint-that translates to a balanced feel at the controls and gives the bike unmatched versatility.
Introducing the Firebird--a must ride for technical bike handlers. John Ker Photo
MEET THE FIREBIRD
The Firebird is an all-mountain design that transcends both the weight and efficiency barriers that plague the genre. In fact, the 167-millimeter-travel (6.57 inches) chassis, outfitted with Shimano XTR and a Fox 36 fork weighs in at 30 pounds and pedals with the brisk feel of a capable cross-country trailbike. The frame geometry is slack enough (67-degree head angle) to ease the Firebird down impossibly difficult rock gardens, but not so far from the reality of cross-country that it can't hold a line up a steep climb.
CLICK HERE for Pivot Firebird Geometry Chart
Chris Cocalis at the South Mountain Trailhead
RC photo
HOW THE FIREBIRD RIDES
Those who are searching for a lightweight, uber-versatile long-travel bike that can handle park-style descents as easily as it can be powered around the back side of the mountain can stop right here. Pivot's Firebird is one of those "ah ha!" mountain bikes that make life-long friendships within five or six revolutions of the crankset. Ours was set up with a lightweight Shimano XTR build, with DT Swiss EX5.D wheels, which gives it a snappy feel under acceleration in spite of its big, 2.35-inch Kenda Nevegal tires.
Proven components reinforce the Firebird's spot-on handling.
Jon Ker photo
Of course, the Pivot tuned dw-link "anti-squat" suspension provides the major boost in the Firebird's pedaling performance-there is little, if any, need to use the Fox RP23 shock's ProPedal lever because the suspension remains silent under power, uphill or on the level. The Firebird is one of the rarest long-travel trailbikes in that it can be powered up a hill or accelerated out of the saddle without the typical discouraging mush with each pedal stroke.
Ride the Firebird from the middle of the bike and it flows easily down and around tricky rock sections. Ease back slightly and it drops off ledges and lands softly. The rear wheel never catches on potholes, logs or rock faces as the Firebird picks its way down technical chutes. Cocalis says that this is due to the suspension's axle path-it falls upward and away from the impact, which gives the rear wheel more time to roll up and over the impasse.
The Frebird's upper link is carbon fiber and the Fox RP23 shock is custom tuned to minimize compression damping forces. John Ker Photo
There is little if any sensation that the rear suspension is affected in a negative manner from braking or pedaling forces, which gives the Pivot a smooth flow over almost any surface and assists technical climbing. With its low, 28-inch stand-over clearance, there is little or no penalty for a forced error on a technical ascent Once we got a feel for the Firebird's climbing ability, we made a game out of clawing our way up and over almost everything in front of the handlebar.
FIREBIRD IN ONE PARAGRAPH
Those who have read this far might believe that we have exaggerated our report in favor of Pivot's Firebird, but the plain fact is that it is such an enjoyable ride that is truly hard to find fault in it-beyond the fact that the day seems too short and the legs and lungs, too weak to completely enjoy a ride like this. Every once and a while a top bike designer falls upon the right combination of knowledge, experience and pure luck, and the resulting magic cannot be improved upon. The Pivot Firebird has that magical feel.
For more info and specifications, CLICK HERE
Pivot uses internal pressed-in bottom bracket bearings to make room for the lower
rocker of the Firebird's dw-link rear suspension. John Ker Photo
DW-LINK: COCALIS STYLE
The aluminum frame is beautifully constructed and is engineered around the dual-link, dw-link rear suspension. Chris Cocalis, once a proponent of the Horst-Link four-bar suspension, chose the dw-link because it can be configured to add firm pedaling performance to full-time bump control. Pivot's first-generation dual-link designs (Mach 4 and Mach 5) exhibited classic dw-link traits-a tendency to ride high in the rear and exhibit some mid-stroke harshness in the suspension feel-but the Firebird has none of these habits. The feel is smooth, almost bottomless, and Cocalis designed a slightly rearward axle path to ease the rear wheel over square edged bumps and uphill stairsteps.
CLICK HERE for more about the Pivot dw-link system.
Cocalis learned a considerable amount from his first two seasons with dw-link suspension. For starters, the shock rates are completely custom tuned at the Fox factory with minimal damping forces. The linkage rates themselves are reconfigured to keep the shock moving through the mid-stroke and, when combined with the rearward axle path, the resulting action feels quite seamless over a wide variety of technical terrain. The firebird rides level, it doesn't squat low in the rear while climbing steeply and it remains balanced and level feeling while descending. Lessons learned from the Firebird led Cocalis to reconfigure the shock rates and setup of the entire Pivot lineup with remarkable results (We will cover the Mach 5 makeover in an upcoming tech feature).
FIREBIRD FRAME DETAILS
Innovative features bristle in and round the Firebird chassis. Its head tube uses a semi-internal 1.5 inch oversized headset to allow the use of any long-stroke fork (Pivot specs a Fox fork with a tapered steerer tube). The bottom bracket shell is unthreaded and a full 95 millimeters wide to allow the lower link pivots to be spaced wide apart for lateral stiffness. The bottom bracket bearings, like the Mach 5, are Shimano's pressed-in type. The lower link incorporates the shock mount for simplicity and space-saving reasons, and the upper link is carbon fiber.
The Firebird's oversized onepointfive head tube and internal headset make room for its profiled top and downtubes. Pivot specs a Fox 36 Float RLC fork with a tapered steerer tube. John Ker photo
The most novel is Pivot's spring-loaded floating front derailleur. It begins life as an '09 Shimano E-type derailleur which is mounted to an aluminum plate which swings on sealed ball bearings. The plate is lifted by a pin on the swingarm so that the tail of the front derailleur remains in relation to the chain as the suspension swings though its arc.
The roller pin on the swingarm (to the left of the bottom bracket shell) contacts the black-anodized tab on the derailleur link when the suspension compresses--which lifts the spring-loaded deralleur link so that the derailleur cage tracks the chain. RC photo
WHY THE PIVOT FLOATING FRONT DERAILLEUR?
For the uninitiated; the front derailleur was designed for a hardtail, not a suspension bike. The bends and curves of the cage are set to contact the chain at specific angles while the chain is riding on each of the three chainrings, and within the range of cassette cogs. When the swingarm cycles through its arc, it moves the chain out of the front derailleur's sweet spots and shifting is compromised. Pivot's solution lifts the front derailleur as the swingarm arcs upwards, keeping the chain in correct relationship with the front derailleur cage. The additional perk of the Pivot front derailleur link is that it is also configured to act as a chain guide-so the Firebird rider can descend or accelerate over the roughest terrain without suffering chain clatter or losing the chain altogether. The system works well. I never lost a chain and shifting was remarkably trouble free no matter what the situation was when I called for a gear change.
HOW THE PARTS STACKED UP
First off, the Pivot's rear suspension was seamlessly matched to its Fox Float 36 fork. Fox has erased the edgy compression feel from the 36 and it feels smooth and sensitive over chatter and rock gardens. Cocalis has a good relationship with Fox, so it comes as no surprise that both ends of the Firebird are in agreement. Another Pivot theme is the Firebird's Magura Marta SL brakes. They stop with authority and rarely drag. The seven inch rotors are well suited for all-mountain use; not too grabby, but one-finger strong. I am a SRAM X.0 a, but I must admit that the new XTR is well suited to the Firebird's easy going manners. Shimano's light feeling shifters and silent-action derailleurs enhance the flowy feeling of the Pivot.
For more pictures and commentary about the Pivot Firebird,
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