Trek Top Fuel 8 Gen 4

Name: Trek Top Fuel 8 Gen 4
Brand: Trek
Price: 3499.00 EUR

2027 MountainTrail Manufacturer page

Price: Not published

Prices shown first for United States
Germany: €3,499 Brand's site · 2026-11-11
United Kingdom: £3,000 Brand's site · 2026-11-11
Travel: 140 / 130 mm Fork / rear shock
Wheels: 27.5″, 29″
Drivetrain: 1 × 12 30t / 10–52t
Gear range: 520%
Weight: 14.88 kg 32.8 lb · Reference configuration not specified
Frame: Aluminum
Brakes: Hydraulic disc

Rider height by size (cm)

Size guide

SM 155–166
SM 155–166
MD 164–177
MD 164–177
MD/LG 173–180
MD/LG 173–180
LG 177–189
LG 177–189
XL 187–195
XL 187–195

Components

19 of 21 identified

Parts found in a manufacturer catalog show their brand, model and key numbers, and the steps show how precisely they are identified: brand, series, model, or the exact product. The info button has every detail and the text the manufacturer published.

Frame and fork

1 part

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 - 130 mm travel Not identified

Suspension

2 parts

Drivetrain

6 parts

Brakes

2 parts

Wheels and tires

5 parts

Front hub
- Bontrager
Rear hub
- Bontrager
Rims
- Bontrager
Spokes

14 g stainless steel, black Not identified
Tires
- Bontrager

Cockpit and contact points

5 parts

Sizes and geometry

10 sizes Open in the geometry plotter

Enter your height to highlight matching ranges.

Size MD/LG

Table

Reach 462mm

Stack 607mm

Wheelbase 1214mm

Head angle 65.5°

Seat angle 76.2°

Every size is drawn to the same scale, in millimeters. Explanatory schematic on an assumed 29″ wheel; exact published values are in the table below.

Size Reported by the manufacturer

Complete manufacturer geometry table 10 published sizes

Complete manufacturer geometry by size
Measurement
Reachmm	417	413	447	442	462	457	477	472	507	502
Stackmm	570	573	603	606	607	611	612	616	630	634
Top tube lengthmm	559	560	588	589	612	613	631	632	673	675
Seat tube lengthmm	360	360	410	410	420	420	435	435	470	470
Head tube lengthmm	105	105	105	105	110	110	115	115	135	135
Head tube angle	65.5°	65°	65.5°	65.1°	65.5°	65.1°	65.5°	65.1°	65.5°	65.1°
Seat tube angle	76°	75.5°	76.9°	76.4°	76.2°	75.7°	75.9°	75.5°	75.2°	74.8°
Chainstay lengthmm	434	435	434	435	439	440	439	440	444	445
Wheelbasemm	1154	1155	1192	1192	1214	1215	1231	1232	1274	1275
Front centermm	721	721	759	759	776	776	793	793	831	831
Bottom bracket dropmm	7	13	23	29	23	29	23	29	23	29
Bottom bracket heightmm	348	342	351	345	351	345	351	345	351	345
Standover heightmm	709	704	759	754	761	756	762	757	767	762
Fork rakemm	42	42	43	44	43	44	43	44	43	44
Trailmm	116	119	124	128	124	128	124	128	124	128
Stack/reach ratio	1.37	1.39	1.35	1.37	1.31	1.34	1.28	1.31	1.24	1.26

Not published by the manufacturer: Front travel, Rear travel, Crank length, Handlebar width, Stem length, Stem angle, Seatpost length and Dropper post travel.

Specifications

Frame and fork

Intended fit: Unisex
Frame material: Aluminum
Bicycle weight: 14.88 kg

32.8 lb
Weight limit: 136 kg

299.8 lb

Suspension

Suspension configuration: Full suspension
Front travel: 140 mm
Rear travel: 130 mm

Drivetrain

Derived by Bikelake

Front chainrings: 1
Smallest chainring: 30
Largest chainring: 30
Rear sprockets: 12
Smallest sprocket: 10
Largest sprocket: 52
Lowest gear: 16.7 in
Highest gear: 87.0 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Seatpost: Dropper seatpost
Shifting: Mechanical

Additional specifications

Bottom bracket standard: BSA
Fork spring: Air
Tire clearance: Maximum tire width: 2.5″
Tire width: 2.4″
Wheel material: Aluminum
Wheel size: 27.5″, 29″

Technical analysis

4 measures

How these figures sit among bicycles of the same class and model year. Context, not a ranking.

Front travel

140 mm

This value is within the central range for this class.

Cohort: Mountain / Trail Model year: 2027
Sample: 333 bicycles with this information
Coverage: 95.4% of the class

Lowest gear

16.7 gear inches

This value is below the central range for this class.

Cohort: Mountain / Trail Model year: 2027
Sample: 273 bicycles with this information
Coverage: 78.2% of the class

Highest gear

87.0 gear inches

This value is within the central range for this class.

Cohort: Mountain / Trail Model year: 2027
Sample: 273 bicycles with this information
Coverage: 78.2% of the class

Shifting

Mechanical

112 of 349 bicycles with this information use electronic shifting.

Cohort: Mountain / Trail Model year: 2027
Sample: 349 bicycles with this information
Coverage: 100.0% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 6.4 km/h
Highest gear: 33.3 km/h

Total gear range 520%

Technical details and class reference

These speeds describe the gearing at the selected cadence, not how fast you can ride.
Calculated from published gear-inch values and their wheel-size assumptions.
These gearing values describe the bicycle, not a selected frame size.
A 100% range means one ratio; 500% means the highest ratio is five times the lowest.
For e-bikes, motor assistance cutoff is not represented.

Gear-inch range

Lower gear-inch values travel less distance per pedal revolution; higher values travel farther.

This bicycle: 16.7–87.0 gear inches
Class reference (p10–p90): 16.7–104.4 gear inches; The band runs from p10 for the lowest gear to p90 for the highest gear.

Cohort: Mountain / Trail Model year: 2027
Lowest gear: 273 bicycles with this information, 78.2% of the class
Highest gear: 273 bicycles with this information, 78.2% of the class

Lineup changes

The published facts that differ across this family's builds and from the same model a year earlier. Missing information never counts as zero.

Differences across 2027 builds
Specification	This bicycle Trek Top Fuel 8 Gen 4	Trek Top Fuel 9.8 Gen 4
Frame
Frame material	Aluminum	Carbon
Bicycle weight	14.88 kg	13.48 kg
Drivetrain
Largest sprocket	52	51
Lowest gear	16.7 in	17.1 in
Cockpit
Shifting	Mechanical	Electronic