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Today’s Deals2026 Trek
Top Fuel 8
A 29″ aluminum frame full suspension trail bike with upper mid-range components.
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Manufacturer Price
$3,999| Weight | 32.1 lbs |
|---|---|
| Frame | Aluminum |
| Suspension | Full, 120 / 130mm |
| Fork | Fox Rhythm Float 34 |
| Shock | Fox Float DPS Performance |
| Wheels | 29″ Aluminum |
| Drivetrain | 1 × 12 |
| Groupset | XT, Deore |
| Brakes | Shimano Deore Hydraulic Disc |
| Seatpost | Dropper |
Based on build material and quality level of the frame, fork, wheelset, groupset, suspension system, and more.
Compare the full Top Fuel model range
View Comparison5'4" – 5'10"
5'8" – 5'11"
5'9" – 6'3"
6'1" – 6'5"
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Summary
The Trek Top Fuel is a versatile trail bike that excels in efficiency and adjustability, offering a lightweight design and stellar climbing performance. However, it faces criticism for its demanding handling and less premium component choices. Its suspension is well-balanced but firmly tuned, making it a mixed bag for riders seeking both comfort and performance.
Very efficient climber
Extensive adjustability options
Lightweight
Good value for money
Precise, reliable shifting even under load
Very little stability at speed
Demanding handling
Underwhelming component choices
Less premium-looking design
Limited freedom of movement on technical trails due to short dropper post
The Trek Top Fuel is the outsider in our 2025 trail bike comparison test, and looks more like a beefed-up XC bike than a true trail bruiser.
Enduro Mountainbike MagazineIt’s a keen climber that balances rider weight well while keeping handling lively and sharp.
off.road.ccThe new Top Fuel responds to your fierce input like an XC bike; the torsionally stiff and responsive frame makes the most of your pedal strokes, and you find yourself moving faster than expected.
Outdoor Gear LabFeedback?
View all reviews
Aug 2025 · Cole Gregg
Trek have done an excellent job with the Top Fuel 9, producing a bike that rips the climbs and still has legs for a rowdy descent.
Jun 2025 · Dario DiGiulio
Honestly, I think Trek could do a slight reshuffle of their lineup. Call this bike the Fuel, and use the 130 / 140mm configuration as the stock setup. That would open the door for a lightweight 120/120 flexstay thing that's truly deserving of the Top Fuel moniker.
Apr 2025 · Simon Kohler
In our 2025 big trail bike comparison test, the Trek Top Fuel 9.8 GX AXS takes on the hottest bikes of the season. How does it fare against the competition?
Very efficient climber
Extensive adjustability options
Very little stability at speed
Demanding handling
Underwhelming component choices
Less premium-looking design
Feb 2025 · Joshua Hutchens
The new Top Fuel is the 4th generation of Trek's lightweight, short-travel trail bike, gaining more versatility and some cool functionality. This...
Adjustable geometry and leverage
Frame storage with BITS
ABP suspension
Bar/stem combo limits adjustability
Heavier wheels
Tires provide a speed limit
Jan 2025
Although raced by Evie Richards on the elite-level cross-country circuit, Trek’s latest Top Fuel 8 Gen 4 is a bike that’ll cater to a raft of tastes thanks to its impressive adaptability. Despite the meagre suspension travel, it dishes out stellar trail manners up and downhill and is primed for UK trails.
Nov 2024 · Spencer Astra
We’re getting deeper into autumn in the Pacific Northwest. This shift leads to slick trails and cooler temperatures. The new Trek Top Fuel seems to be the perfect companion to scoot around the mountain and dodge puddles. This bike immediately caught my attention, delivering an unexpectedly fun and efficient experience in a sleek, trail-friendly package. With a lightweight, carbon frame and components tuned for speed and control, the Top Fuel has quickly become a bike I look forward to riding.
Oct 2024
3 months aboard the 9.8 GX AXS version of Trek's XC-plus, trail-lite, most of the bell curve-targeted Top Fuel
Excellent pedaling and climbing efficiency
Cohesive and balanced design
Quiet and composed ride
Great handling and stability at speed
High-quality frame and fit/finish
Adjustable geometry via flip-chip
Saddle (Trek Verse Comp) uncomfortable for reviewer
Dropper post (Bontrager Line) had fore/aft play
Brakes (SRAM Level Bronze) lacked bite on long descents
Integrated bar/stem (RSL) stiff, causing hand fatigue
Heavy wheelset (~2000g) on a $7000 carbon bike
Overall bike weight ~30lbs
Oct 2024 · Jeff Barber
The Trek Top Fuel is a short-travel mountain bike that tries to do a lot of things, though I found it's really an XC bike at heart.
Efficient pedaling, as long as the climbing is shock set to firm
A joy on descents
Bontrager components are surprisingly solid
Not as comfortable or playful as other downcountry bikes
Fit might be tricky for some riders
Can’t get away with leaving the shock open for the whole ride
| Frame | Alpha Platinum Aluminum, internal storage, tapered head tube, internal guided routing, downtube guard, alloy rocker link, 4-way Mino Link, ABP, Boost148, 120mm travel BB Standard: BSA, 73mm, Threaded Tire Clearance: 2.5" Colors: Matte Dark Web; Lichen Green |
|---|---|
| Fork | Fox Rhythm 34, Float EVOL air spring, GRIP damper, tapered steerer, 44mm offset, Boost110, 15mm Kabolt axle, 130mm travel Travel: 130mm Spring Type: Air |
| Shock | Fox Performance Float DPS, 2-position damper, 185mm x 50mm Travel: 120mm |
| Bottom Bracket | Shimano BB-MT501 BSA |
| Stem | Bontrager Elite, 35mm, 0 degree, 45mm length |
| Handlebar | Bontrager Line, alloy, 35mm, 27.5mm rise, 780mm width |
| Saddle | Bontrager Verse P3, chromoly rails |
| Seatpost | Size: S, Bontrager Line Dropper, 100mm travel, MaxFlow, internal routing, 34.9mm, 310mm length; Size: M, ML, L, XL, Bontrager Line Dropper, 170mm travel, MaxFlow, internal routing, 34.9mm, 450mm length Type: Dropper |
| Grips | Bontrager XR Trail Comp, nylon lock-on |
| Rear Derailleur | Shimano XT M8100, long cage |
|---|---|
| Crank | Shimano Deore M6120, 30T ring, 55mm chainline, 170mm length |
| Shifters | Shimano XT M8100, 12 speed |
| Cassette | Shimano SLX M7100, 10-51T, 12 speed |
| Chain | Shimano SLX M7100, 12 speed |
| Brakes | Shimano 4-piston hydraulic disc, M6100 lever, M6120 caliper Type: Shimano Deore Hydraulic Disc |
| Rims | Front: Size: S, Bontrager Line Comp 30, Tubeless Ready, 6-bolt, Boost110, 15mm thru axle, 27.5''; Size: M, ML, L, XL, Bontrager Line Comp 30, Tubeless Ready, 6-bolt, Boost110, 15mm thru axle, 29'', Rear: Size: S, Bontrager Line Comp 30, High Strength 6000 Series Aluminum rim, Tubeless Ready, Rapid Drive 108, 6-bolt, Shimano MicroSpline freehub, Boost148, 12mm thru axle, 27.5''; Size: M, ML, L, XL, Bontrager Line Comp 30, High Strength 6000 Series Aluminum rim, Tubeless Ready, Rapid Drive 108, 6-bolt, Shimano MicroSpline freehub, Boost148, 12mm thru axle, 29'' |
|---|---|
| Tires | Size: S, Bontrager Gunnison Pro XR, Tubeless Ready, wire bead, 60 tpi, 27.5x2.40''; Size: M, ML, L, XL, Bontrager Gunnison Pro XR, Tubeless Ready, dual compound, aramid bead, 60 tpi, 29x2.40'' |
| Disc Rotors | Shimano RT66, 6-bolt, 180mm |
First added December 24
Last updated July 19
Not listed for 314 days