BIKE TEST – Specialized S-Works Stumpjumper FSR Carbon 29
>> 2012 is definitely the year of the all-mountain 29er. In Europe, skepticism towards large wheels in cross-country has not yet vanished. That’s why we’ve been asking ourselves a big question: does the pricey 29er version of the legendary Stumpjumper FSR have the potential to continue the classic’s story of success?
The Stumpjumper. For the last 30 years, this iconic bike has successfully managed to maneuver its way through a lot of competitive terrain. The first Specialized model substantially shaped the foundation of bike history. As one of the first mountain bikes in production, it also represents a true icon of a sport. During its 30 years of development – beginning with Stumpjumper FSR providing one of the first full-suspension-designs ever – the design has traveled a long way to reach its latest development stage. What once began as the Stumpy-master-form with a heavy steel frame, massive motorbike-like brake levers and “zero suspension” back in the 1980’s is now aiming to embody the peak of bike development.
To be specific: not just any bike – no – the engineers from Morgan Hill, California, claim to have created “THE most capable bike in the world” with the Stumpjumper FSR S-Works 29. To underline this, the muscular carbon main frame radiates self-confidence, which is supported by the FSR four-bar rear suspension system, also made of carbon. Outcome? A stunningly light chassis of 2300 g (including rear shock), which is supposed to easily resist the high strains of all-mountain terrain.The main frame is a compound of two monocoque-modules which are supposed to be highly resilient because of the carbon which joins the tube segments. Specialized responds to the wide-spread skepticism regarding the frame stiffness of 29ers pragmatically: design details like the PressFit 30 crank set, the tapered head tube, and the 142mm dropouts with a 12mm thru-axle at the rear wheel should clear out any doubts.
The four-bar suspension system works with the Fox RP-23 rear shock with exclusive low-friction Kashima coating; using the remote Brain platform, the rider can individually adjust the rear shock from extremely active to a very firm platform. The 130 mm of rear travel complements the Fox Float Factory F130 fork.
In addition to the Brain element, the rear suspension features another highlight: the AUTOSAG of the Fox/Specialized rear shock allows a simple sag adjustment via an additional valve. To do this, the rider first fills the rear shock at the main valve (three times body weight in kg in psi), gets on the bike and uses the red valve. Superfluous air streams out via the valve, which then adjusts the air pressure in the positive and negative chambers automatically according to the rider’s weight.
It’s almost possible to forget biking over the loads of love for detail. Almost! With a 603 mm top tube and a compact 100 mm head tube in medium size, the seating position is sporty and the rider sits nicely centered on the bike.
The first uphill at moderate pitch makes us smile: thanks to the light 11.5 kg weight, feel-good geometry and the 1530 g Roval carbon wheels, the Stumpy 29er loves speed! A good pedaling position proves the dedicated geometry on steep climbs: a seat angle of 74.5° is paying off right now. The FSR rear suspension, constantly seeking traction, shows off its skill-set in rough sections uphill. Due to the naturally high-traction 29er tires, the bike manages to carry admirable speed. In addition to the superior traction, another remarkable difference in regards to the 26er is apparent, thanks to the almost unshakable performance uphill: if the rider happens to get off the ideal racing line, the bike will fix it.
Even on narrow trails the Stumpy FSR 29 is a pure joy to ride: weight shifts to the front or the back are easy, and the bike has no problem with fast turns. However, the rider has to familiarize himself with the 29er all-mountain’s special characteristics in quick serpentine curves:
the longer wheelbase needs to be taken into account, as well as a slight change in timing for turn-ins.
This is where the 720 mm-wide handlebar comes in handy. Active riders who like to jump often praise the feeling of 26ers, which is the only shortcoming of the AM 29er – it is too plush and confident on the trail to achieve this feeling. This is an impression that the Stumpy FSR 29 eventually confirms on potholed trails and big airs: the combination of a sensitive but very forgiving chassis and the lower roll-over angle of the large wheels keep the bike and its rider firmly and reliably on the ground. (Even on tracks that are typically used for enduro!) The Stumpy 29er’s features are designed for blasting down gnarly trails – the bashguard protects the chainring, the “Dangler“ 30 g light chain guide securely contains the chain, and the Command adjustable seatpost makes stopping to lower your seat completely needless.
Conclusion: To sum it up, the 7599 €-worthy Stumpjumper FSR S-Works 29 is a real technical highlight. It is an enormously versatile 29er all-mountain bike. It suits a marathon as well as an enduro race or a technically sophisticated crossing of the Alps. The well-established 26erAM has to face some real competition in the upcoming years with wheels of this kind. Their unusually smooth riding characteristics offer serious advantages – and not only for beginners!
More info: www.specialized.com Photo: Sebas Rombero Text: Florian Storch