Tech feature: Trek 2009 MTB introduction, July 23, 2008
Trek Bicycles unveiled the 2009 version of its Fuel EX line of trail mountain bikes in Durango, Colorado, with an all-new full-carbon bike headlining a revamped range that Trek says is lighter and stiffer than its predecessors. Trek mountain bike product manager John Riley explained that the new carbon bike sprung from an effort to meld the stiffness of previous aluminum Fuel EXes with the light weight of the 2008 carbon bike - and to beat the weight of previous versions.
Aimed at general mountain biking and in particular endurance racing, the top-of-the-line 2009 Fuel EX 9.9 has a claimed weight of 10.66kg (23.5lb), on a 2.2kg (4.96lb) frame (with shock).
Several new technologies have helped get the bike under 24lb such as the 'net moulding' technique borrowed from the new Madone that directly integrates bearing seats for the suspension pivots and 95mm-wide BB95 bottom bracket shell.
Net moulding saves weight by eliminating aluminium hard points but the BB95 design also allows for a larger down tube, stiffening the frame against lateral and torsional flex. At the front end, Trek's E2 head tube with 1 1/2in lower bearing also provides more space for a big down tube. The practical upshot is a 28 percent stiffer frame on Trek's axle to axle test, Riley said.
Top-end Fuels also get an OCLV moulded carbon link instead of the previous Fuel's magnesium unit which saves 35g. The total upshot is that the 2008 carbon frame weighed 2450g; the 2009 is down to 2,238g.
New shocks tweak the ride
But Trek hasn't just gone only for the weight-weenie vote. The company's ongoing cooperation with shock maker Fox has led to a custom-tuned version of Fox's new XV rear can to improve the suspension performance.
The special edition shock has a less progressive curve in the latter half of its travel, and a wider range of rebound damping so it works for a wider range of riders.
The recent development of Trek's suspension bikes has been driven by Jose Gonzalez and Greg Buhl in the development office Trek opened a while ago in Santa Clarita, California.
That's been a big step forward for Trek as the wide variety of trails within an hour and a half of base means Buhl, Gonzalez and their test riders can put the bikes through their paces far more thoroughly than they could in rural but rather flat Wisconsin.
On the trail
First ride impressions of the Fuel EX were a bit lukewarm. But the next day I switched from a 17.5in frame to an 18.5in and had Jared Connell of Fox Racing Shox carefully tune the set up for me, most importantly increasing the sag from 25 to 30 percent.
The result was a revelation as the bike became far better coupled to the trail and more comfortable without losing any of the accuracy that comes from the frame's impressive lateral and torsional rigidity.
Durango's Hermosa Creek Trail is mostly downhill, but it's shallow enough that you're pedaling a lot. Also, while it's not overly rocky it's twisty enough that you have to pay constant attention., The Fuel EX was a perfect partner as I barreled along, responding calmly and accurately to changes of speed and direction and getting me out of trouble more times than I can remember as I went into corners and off-cambers a bit too hot. Of course, if its handling and suspension weren't so good, I would never have been in high-speed trouble in the first place, but that's the fun factor of this bike.
The first Fuel EX I rode had a slight tendency to wag its head on climbs. Nothing you couldn't live with, but slightly annoying in a bike that otherwise surged uphill with distinct enthusiasm. Whether it was the better suspension tune allowing the fork to sit a little deeper in its range or the longer top tube of the 18.5in frame, the second bike I rode was perfectly mannered on the uphills.
It ploughed up and over obstacles and was completely unfazed when I stood and thrashed as clumsily as possible to sprint past Mountain Biking UK test editor Steve Worland on one of the last short pitches. The control and calm of the Fox-powered suspension is deeply flattering.
Trek and Fox have crafted a superb trail bike in the 2009 Fuel EX. It's well-mannered and controlled without being dull and inspires you to push as hard as possible in twisty singletrack and wide-open trails alike. Barring very steep and/or overly rocky terrain, our early indications suggest this will make an excellent one-bike-fits-all machine that will suit the endurance racer or all-day rider alike.