2025 Trek Top Fuel 9.8 XT Gen 4
The Top Fuel 9.8 XT Gen 4 is a lightweight carbon trail bike built to rip up climbs and stay playful on descents. It gives you the confidence you want through roots and rocks, thanks to a 120 mm/130 mm RockShox suspension package with a Pike Select+ fork and Deluxe Ultimate shock. Plus, you get clean shifts from a 12-speed Shimano XT drivetrain.
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OVERVIEW
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SPECS
It's right for you if...
You're after a carbon trail bike that keeps weight to a minimum without compromising on capability. You like to ride everything – long alpine climbs, rooty aspen slalom, fast XC singletrack and you want a bike that can keep up on the ups and hold its own on the downs. Keeping things light with a carbon frame is important to you, and you want the light yet precise shifting of a Shimano XT drivetrain.
The tech you get
An OCLV Mountain Carbon frame with a 4-way Mino Link lower shock mount for tweaking geometry and suspension leverage rate. A 130 mm RockShox Pike Select+ fork with DebonAir spring, and Charger 3.1 RC2 damper, plus 120 mm of rear travel from a RockShox Deluxe Ultimate RCT shock. A Shimano XT 12-speed drivetrain, Shimano XT 4-piston hydraulic brakes, Bontrager Line dropper post and tubeless-ready Bontrager Line Comp 30 wheels.
The final word
If you're after a light carbon trail bike that balances a playful and capable ride, reach for Top Fuel 9.8 XT Gen 4. Its ultra-lightweight frame pairs with a 4-way Mino Link lower suspension mount for taking control of your geometry and suspension feel. Plus, you get clean shifts from a Shimano XT drivetrain and a sweet RockShox suspension package.
Why you'll love it
The Top Fuel Gen 4 delivers with an intensely lightweight build, improved in-frame storage and more adjustability for all kinds of rides and riders
With 120 mm rear and 130 mm front RockShox suspension, it delivers a well-balanced ride that stays efficient on the ups and playful on descents
The 4-way Mino Link makes it easy to adjust your geometry or leverage rate for how and where you want to ride
In-frame storage with an improved BITS bag system makes it easy to stash tools, tubes and snacks
It's more upgrade-ready than ever, with room for bigger 140 mm forks and longer-stroke shocks for up to 130 mm of rear travel, plus room for extra-long dropper posts
*Please note – spec applies to all sizes unless listed separately
Frameset
Frame OCLV Mountain Carbon, internal storage, tapered head tube, internal guided routing, downtube guard, OCLV Next rocker link, Mino 4 link, ABP, Boost148, 120 mm travel
Shock RockShox Deluxe Ultimate RCT, 185 mm x 50 mm
Max compatible fork travel 140 mm
Wheels
*Wheel front Size: S
Bontrager Line Comp 30, Tubeless Ready, 6-bolt, Boost110, 15 mm thru axle, 27.5"
Size: M, ML, L, XL
Bontrager Line Comp 30, Tubeless Ready, 6-bolt, Boost110, 15 mm thru axle, 29"
*Wheel rear Size: S
Bontrager Line Comp 30, High Strength 6000 Series Aluminium rim, Tubeless-Ready, Rapid Drive 108, 6-bolt, Shimano MicroSpline freehub, Boost148, 12 mm thru axle, 27.5"
Size: M, ML, L, XL
Bontrager Line Comp 30, High Strength 6000 Series Aluminium rim, Tubeless-Ready, Rapid Drive 108, 6-bolt, Shimano MicroSpline freehub, Boost148, 12 mm thru axle, 29"
Skewer rear Bontrager Switch thru-axle, removable lever
*Tyre Size: S
Bontrager Gunnison RSL XT, Tubeless-Ready, triple compound, aramid bead, 120 tpi, 27.5x2.40"
Size: M, ML, L, XL
Bontrager Montrose RSL XT, Tubeless-Ready, triple compound, aramid bead, 120 tpi, 29x2.40"
Size: M, ML, L, XL
Bontrager Gunnison RSL XT, Tubeless-Ready, triple compound, aramid bead, 120 tpi, 29x2.40"
Rim strip Bontrager TLR
Max tyre size Frame: 29x2.50", Fork: See manufacturer
Drivetrain
Shifter Shimano XT M8100, 12-speed
Rear derailleur Shimano XT M8100, long cage
Crank Shimano XT M8120, 30T, 55 mm chain line, 170 mm length
Bottom bracket Shimano BB-MT501 BSA
Cassette Shimano XT M8100, 10-51, 12-speed
Chain Shimano Ultegra/XT M8100, 12-speed
Max. chainring size 1x: 34T, min 30T
Components
Saddle Verse Short Comp, steel rails, 145 mm width
*Seatpost Size: S
Bontrager Line Dropper, 100mm travel, MaxFlow, internal routing, 34.9 mm, 310mm length
Size: M, ML, L, XL
Bontrager Line Dropper, 170 mm travel, MaxFlow, internal routing, 34.9 mm, 450 mm length
Grips Bontrager XR Trail Elite, nylon lock-on
Brake Shimano XT M8120 4-piston hydraulic disc
Brake rotor Shimano RT86, 6-bolt, 180 mm
Rotor size Max brake rotor sizes – Frame: 200 mm, min 180 mm, Fork: see fork manufacturer
Accessories
Bag Bontrager BITS Internal Frame Storage Bag
Weight
Weight M - 13.45 kg / 29.66 lbs (with TLR sealant, no tubes)
Weight limit This bike has a maximum total weight limit (combined weight of bicycle, rider and cargo) of 136 kg (300 lb).
We reserve the right to make changes to the product information contained on this site at any time without notice, including with respect to equipment, specifications, models, colours, materials and pricing. Due to supply chain issues, compatible parts may be substituted at any time without notice.
Bike and frame weights are based on pre-production painted frames at time of publication. Weights may vary in final production.
Shipping
We aim to have each order fulfilled and shipped within 3-5 working days after your order being paid.
Link to your shipping policy.
Delivery
Shop online at biket and choose between 2 convenient delivery options.
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Door-to-door courier countrywide.
Refunds
Please note we do not offer straight refunds, these are issued as store credits only.
WHO ARE WE
Biket is one of South Africas Top Online Cycling Stores, based in Hillcrest, KZN.
We offer a range of the highest quality cycling products from Trek bikes, Giant bikes, Scott bikes, Bontrager & Oakley apparel, and a full service centre. Our aim is to offer the highest quality cycling products paired with the best advice.
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