The Trek Top Fuel 9.9 XX AXS Gen 4 is an ultra-light and capable carbon trail bike that's built for soaring up climbs and rallying over miles of singletrack. This top-level build delivers the performance you want, with a RockShox Ultimate suspension package (120 mm/130 mm) and SRAM's lightest wireless XX AXS transmission that shifts smooth and easy, especially under load. It's topped off with carbon wheels to keep your ride light from top to bottom.
Sunset Cycles offers the 2025 Trek Top Fuel 9.9 XX AXS Gen 4 trail bike in Matte Dark Web finish with free delivery.
The 2025 Trek TOP FUEL (CARBON) range: Top Fuel 9.8 GX AXS Gen 4 (Black) | Top Fuel 9.9 X0 AXS Gen 4 (Black) | Top Fuel 9.9 XX AXS Gen 4 (Black)
| Frame & Fork | |
| 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 |
| Fork | |
| Shock | RockShox Deluxe Ultimate RCT, 185 mm x 50 mm |
| Wheels & Tyres | |
| Wheel front | Size: S Bontrager Line Pro 30, OCLV Mountain Carbon, Tubeless Ready, 6-bolt, Boost110, 15 mm thru-axle, 27.5" Size: M, ML, L, XL Bontrager Line Pro 30, OCLV Mountain Carbon, Tubeless Ready, 6-bolt, Boost110, 15 mm thru-axle, 29" |
| Wheel rear | Bontrager Line Pro 30, OCLV Mountain Carbon, Tubeless-Ready, Rapid Drive 108, 6-bolt, Boost148, 12 mm thru axle |
| Tyre | Size: S Bontrager Gunnison RSL XT, Tubeless-Ready, triple compound, aramid bead, 120 tpi, 27.5x2.40" Size: M, ML, L, XL Bontrager Gunnison RSL XT, Tubeless-Ready, triple compound, aramid bead, 120 tpi, 29x2.40" |
| E-system | |
| Battery | SRAM eTap battery pack (with charger) |
| Drivetrain | |
| Shifter | |
| Rear derailleur | SRAM XX SL Eagle AXS, T-Type |
| Crank | SRAM XX Eagle, DUB, 30T, T-Type, 55 mm chainline, 170 mm length |
| Bottom bracket | SRAM DUB MTB Wide, 73 m, BSA threaded |
| Cassette | SRAM Eagle XS-1299, T-Type, 10-52, 12-speed |
| Chain | SRAM XX Eagle, T-Type, 12-speed |
| Components | |
| Saddle | Verse Short Pro, carbon rails, 145 mm width |
| Seatpost | Size: S RockShox Reverb AXS, 100 mm travel, wireless, 34.9 mm, 340 mm length Size: M, ML, L, XL RockShox Reverb AXS, 170 mm travel, wireless, 34.9 mm, 480 mm length |
| Handlebar/stem (integrated) | Size: S Bontrager RSL Integrated handlebar/stem, OCLV Carbon, 27.5 mm handlebar rise, 820 mm width, 0-degree stem rise, 35 mm stem length Size: M, ML, L, XL Bontrager RSL Integrated handlebar/stem, OCLV Carbon, 27.5 mm handlebar rise, 820 mm width, 0-degree stem rise, 45mm stem length |
| Grips | |
| Brake | SRAM Level Ultimate 4-piston hydraulic disc |
| Brake rotor | SRAM HS2, 6-bolt, 180mm |
| Rotor size | Max brake rotor sizes – Frame: 200 mm, min 180 mm, Fork: see fork manufacturer |
| Weight | |
| Weight | M - 12.85 kg / 28.33 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. | ||