Top Fuel 8 Gen 4 - 2025

It's right for you if...

You want an alloy full suspension that's ready to rip. You like to ride everything from cross-country hot laps to all-mountain adventures, and you need a bike that's light, versatile and confident. You've got an appreciation for the durability of aluminium, but want upgrades where they matter, like your drivetrain and suspension.

The tech you get

An Alpha Platinum Aluminium frame equipped with a 4-way Mino Link lower shock mount for tweaking geometry and suspension leverage rate. A 130 mm FOX Rhythm 34 fork with Float EVOL air spring and GRIP damper, plus 120 mm of rear travel from a FOX Performance Float shock with a 3-position damper. It's topped off with a Shimano XT/SLX 12-speed group set, hydraulic disc brakes, a Bontrager Line dropper post and Tubeless Ready Bontrager Line Comp 30 wheels.

The final word

The Top Fuel 8 Gen 4 is ready to cut loose from all-day climbs to rooty descents. It balances capability and efficiency, with just enough travel to keep the ride smooth without eating up your pedalling power. It gives you the perfect blend of affordability, with a rugged alloy frame and upgrades where they matter, like the Shimano XT/SLX drivetrain.

Why you'll love it

• Its lightweight frame and versatile geometry make it the perfect choice for all kinds of rides and all kinds of riders
• The 4-way Mino Link makes it easy to adjust your geometry or leverage rate for how and where you want to ride
• You get a sweet balance of price and performance with upgraded components and a rugged alloy frame
• The Alpha Platinum Aluminium frame is robust, yet light, and packs in updated internal frame storage for easy access to gear 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

SPECS

FRAMESET

Frame: Alpha Platinum Aluminium, internal storage, tapered head tube, internal guided routing, downtube guard, alloy rocker link, 4-way Mino Link, ABP, Boost148, 120 mm travel

Fork: Fox Rhythm 34, Float EVOL air spring, GRIP damper, tapered steerer, 44 mm offset, Boost110, 15 mm Kabolt axle, 130 mm travel

Shock: Fox Performance Float DPS, 3-position damper, 185 mm x 50 mm

Max compatible fork travel: 140 mm

WHEEL

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, Tubeless Ready, Rapid Drive 108, 6-bolt, Boost148, 12 mm thru axle, 27.5"

- Size: M, ML, L, XL | Bontrager Line Comp 30, Tubeless-Ready, Rapid Drive 54, 6-bolt, Boost148, 12 mm thru axle

Skewer rear: Bontrager Switch thru-axle, removable lever

Tyre:

- 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"

Tyre part: Bontrager TLR sealant, 180 ml/6 oz

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 Deore M6120, 30T ring, 55 mm chainline, 170 mm length

Bottom bracket: Shimano BB-MT501 BSA

Cassette: Shimano SLX M7100, 10-51T, 12-speed

Chain: Shimano SLX M7100, 12-speed

Max. chainring size: 1x: 34T, min 30T

COMPONENTS

Saddle: Bontrager Verse P3, chromoly rails

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

Handlebar: Bontrager Line, alloy, 35 mm, 27.5 mm rise, 780 mm width

Grips: Bontrager XR Trail Comp, nylon lock-on

Stem: Bontrager Elite, 35 mm, 0-degree, 45 mm length

Brake: Shimano 4-piston hydraulic disc, M6100 lever, M6120 calliper

Brake rotor: Shimano RT66, 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 - 14.58 kg / 32.15 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).

The manufacturer reserves 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. The prices shown are the manufacturer's suggested retail prices.