The Trek Top Fuel 8 Gen 4 is a nimble alloy trail bike that strikes a balance between quick climbing efficiency and descending confidence. It packs in a versatile 130 mm front and 120 mm rear travel for ripping over rocks and roots without sacrificing power on ascents. It's built from lightweight Alpha Platinum Aluminium that helps save your budget for bike trips, but packs in upgrades where they matter, like a 12-speed Shimano XT and SLX drivetrain, and a Fox Rhythm 34 fork.
Sunset Cycles offers the 2025 Trek Top Fuel 8 Gen 4 trail bike in Matte Dark Web finish with free delivery.
The 2025 Trek TOP FUEL (ALLOY) range: Top Fuel 5 Gen 4 (Mercury) | Top Fuel 8 Gen 4 (Black) | Top Fuel 9 Gen 4 (Juniper)
| Frame & Fork | |
| Frame | Alpha Platinum Aluminium, internal storage, tapered head tube, internal guided routing, downtube guard, OCLV Next rocker link, Mino 4 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 |
| Wheels & Tyres | |
| Wheel front | Bontrager Line Comp 30, Tubeless Ready, 6-bolt, Boost110, 15 mm thru axle |
| Wheel rear | Bontrager Line Comp 30, Tubeless-Ready, Rapid Drive 54, 6-bolt, Boost148, 12 mm thru axle |
| 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" |
| 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 |
| 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). |
| Frame Size | Rider Height* (metric) | Rider Height* (imperial) |
| Small | 155 - 165 cm | 5'1" - 5'5" |
| Medium | 165 - 176 cm | 5'5" - 5'9" |
| Medium/Large | 173 - 180 cm | 5'8" - 5'11" |
| Large | 177 - 188 cm | 5'10" - 6'2" |
| X Large | 188 - 195 cm | 6'2" - 6'5" |
| *This is for guidance only. You may be taller or shorter, it doesn't mean our bikes will not fit you. The best way to determine the correct bike size for you is to try one. Please contact us if you are in any doubt about the correct bike size for you. | ||