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By Singletrack.com Test Crew
When you’re dropping upwards of five grand on a bicycle, well then, you expect a lot of bicycle in return.
And with Trek’s Top Fuel 9.8 the deliverables are plenty. Among other things there’s the made-in-the-USA OCLV carbon frame with the fat, net-molded bottom bracket and headtube for direct-fit bearings. The bike’s extended seat tube saves weight, accepting a stubby seatpost that’s available in different lengths and setbacks to accommodate riders of different proportions.
Trek’s suspension system is as sophisticated as it gets, with forward reaching chainstays serving as the lower shock mount (a design called Full Floater, which Trek says boosts small-bump sensitivity). Out back, the ABP rear dropouts help isolate braking input and keep the suspension moving when the binders are puckered.
So, yes, all of Trek’s in-house brainpower delivers on the rocket that is the four-inch travel bike that is the Top Fuel.
Our testers, by and large, were impressed with the Top Fuel’s ride characteristics. But that doesn’t necessarily mean that everyone’s take on the 23.88lb (size large as tested) rig was unanimous.
However, the one adjective that came out of most everyone’s turns on the bike was fast — as in quick, snappy, and responsive. From climbing to cornering to accelerating, the Top Fuel felt like it wanted to race.
“It’s very agile in corners, but predictable,” said one tester. “It’s got quick tip-in to turns, but not so much that it feels twitchy and nervous. Plus it’s stable enough at speed to be able to outrun the travel. It really begs you to rip harder and faster.”
Our riders of smaller stature said the Top Fuel was plenty stiff in the front and rear. That translated into the bike’s overall snappy attributes. Their impressions were that the bike is light and it holds traction nicely through hard cornering.
That went the same for climbing technical trail, where the bike’s quick-flick handling made formidable ledges cleanable while maintaining rear-end power transfer to the ground. What aids there is that the back end is tucked up tightly enough to offer traction on steep climbs.
Bigger, more physical riders also found that the rear-suspension performed well; supple under power and braking with excellent small-bump pickup. High frequency trail chatter disappeared, thanks to the Full Floater and ABP suspension design.
On the other hand, the end stroke felt almost bottomless, but ramped up on big hits just enough to let riders know their four inches of fame were up. At the same time it felt efficient both in the saddle and out.
But what was also discernable for our more physical riders was how the Top Fuel’s front end felt.
“It’s plush in the back,” said a 200-pound tester. “But it definitely had a more cross-country feel with a slightly flexy front end; for my style that’s going to be noticeable.”
On the plus side, a Fox 32 F-Series fork up front helped add rigidity to maintain steering precision, whereas a RockShox SID might have compounded the issue, making the Top Fuel less rigid on the front end than some riders would prefer. The bottom bracket area was stout enough to provide stable, powerful power input with no negative attributes.
Even with the flex issue, the Top Fuel works climbing, pedaling the flats and descending alike. While the front end may not be the stiffest overall the Top Fuel will get the job done without problem – accurate uphill and down without need to second guess.
So is there a line drawn out on the trail that the Top Fuel shouldn’t cross? Our group of testers, which included a variety of riding styles and preferences, came to the conclusion that for most riders, the Top Fuel is best used as a cross-country bike.
“This is a very nimble and supple four-inch XC bike,” a tester said. “But there’s no mistaking it for a five-inch bike.”
That’s not to be taken as a slight. The Top Fuel is what it is: An unabashed, all-around rocket race bike that makes you want to hit the throttle coming out of every corner or when the situation involves gaps — as in closing or opening one. And when it comes to bagging that last hill the Top Fuel is all help, not a hindrance.
“It climbs like a proper cross-country race bike,” said a tester, “very quick.”