Top Fuel 8 Gen 4
OverviewAbout the Trek Top Fuel 8 Gen 4
The Trek Top Fuel 8 Gen 4 is a mountain bike, built on a aluminium frame, listed at $4,499.99. An off-road bike for trails, with grippy tyres and trail-ready geometry.
SizingWhat size Top Fuel 8 Gen 4 do I need?
Enter your height to see the size Trek recommends.
| Size | Rider height | In feet | Inseam |
|---|---|---|---|
| S | 155 to 165 cm | 5 ft 1 in to 5 ft 5 in | 74 to 78 cm |
| M | 165 to 177 cm | 5 ft 5 in to 5 ft 10 in | 79 to 83 cm |
| ML | 173 to 180 cm | 5 ft 8 in to 5 ft 11 in | 81 to 86 cm |
| L | 177 to 188 cm | 5 ft 10 in to 6 ft 2 in | 84 to 89 cm |
| XL | 188 to 195 cm | 6 ft 2 in to 6 ft 5 in | 89 to 91 cm |
Rider heights from Trek's size chart. Height is a starting point: arm and leg length, flexibility and riding style all matter, so a test ride beats any chart. How bike sizing works.
SpecificationsWhat we know
- Brand
- Trek
- Model year
- 2027
- Category
- Mountain
- Frame
- Aluminium
- Wheel size
- 29-inch (27.5-inch on the smallest sizes)
- Drivetrain
- SRAM Eagle 70 T-Type 1x12
- Brakes
- Disc
- Frame sizes
- S, M, ML, L, XL
- Price
- $4,499.99, RRP AUD (Trek Australia, checked 16 Oct 2026)
Specs and pricing are listed in AUD and sourced from Australian retail listings. Confirm the current details and availability with the seller before purchase.
GeometrySize M
- Stack
- 603 mm
- Reach
- 447 mm
- Stack/reach
- 1.35
- Head angle
- 65.5 deg
- Seat angle
- 76.9 deg
- Wheelbase
- 1192 mm
- Chainstay
- 434 mm
- BB drop
- 23 mm
- Standover
- 759 mm
- Fork rake
- 43 mm
GearingRatios
Ratios are derived from the chainrings and cassette. They describe the gearing, not any rider's ability.
Drivetrain & buildFull specification
- Groupset
- SRAM Eagle 70 T-Type
- Shifting
- Mechanical
- Drive
- 1x
- Speeds
- 12
- Crank
- SRAM Eagle 70, DUB, 30T steel, T-Type, 55 mm chainline, 170 mm length
- Chainrings
- 30
- Cassette
- SRAM Eagle XS-1270, T-Type,10-52, 12-speed
- Rear derailleur
- SRAM Eagle 70, T-Type
- Brakes
- SRAM DB 8 4-piston hydraulic disc
- Rotors
- 180mm
- Wheelset
- Bontrager Line TLR 30, Tubeless-Ready, 28-hole, Presta valve
- Stock tyre
- 29x2.40
- Tubeless
- Yes
- Fork material
- Fox Rhythm 34, Float EVOL air spring, GRIP damper, tapered steerer, 44 mm offset, Boost110, 15 mm Kabolt axle, 140 mm travel
- BB standard
- SRAM DUB MTB Wide, 73 m, BSA threaded
- Seatpost
- Bontrager Line Dropper, 170 mm travel, MaxFlow, internal routing, 34.9 mm, 450 mm length
- Cockpit
- Bontrager Elite, 35 mm, 0-degree, 45 mm length / Bontrager Line, alloy, 35 mm, 27.5 mm rise, 780 mm width
- Saddle
- Verse Short Comp, steel rails, 145 mm width
SuspensionMTB detail
- Front travel
- 140 mm
- Rear travel
- 130 mm
- Fork
- Fox Rhythm 34
- Fork stanchions
- 34 mm
- Shock
- Fox Performance Float
- Wheel config
- 29
- Dropper
- Bontrager Line Dropper
- Dropper travel
- 170 mm
- Discipline
- Downcountry
- Suspension
- full suspension
Bike DNAWhat the numbers say
- Steering
- A 65.5 deg head angle points to slack, trail and enduro handling.
- Climbing
- Lowest ratio 0.58 is a very low climbing gear for steep or loaded climbs.
Derived from the published geometry and gearing above. It describes the numbers, not a ride test.
BikeFinder Data Profile: geometry and specification researched from published sources (Trek Australia product data 74824 (spec list, geometry chart, size chart)), verified 2026-10-16. This is a specification analysis, not a physical ride review.
Where to buyStockist
BikeFinder is an independent directory. We link to retailers; prices and stock are set by the seller and shown as at the date checked.
