Why is this a must-have top mountain bike? [Trek Top Fuel 9.9 XX AXS Gen 4 Review ]

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Trek Top Fuel 9.9 XX AXS Gen 4 Review

• Price: $ 10,499.99
• Frame: OCLV Mountain Carbon
• Max tire size  Frame: 29×2.50″, Fork: See manufacturer
• Weight: M – 12.85 kg / 28.33 lbs (with TLR sealant, no tubes)

What we like about it: Ultra lightweight structure, improved storage, multi-directional adjustable.

What we didn’t like about it: Slightly expensive price.

Rating: (4.9/5)

Embrace nature and challenge the limits! The Trek Top Fuel 9.9 XX AXS Gen 4 features an ultra light carbon fiber frame and top-notch RockShox Ultimate suspension system, making it easy to handle rough mountain roads and sudden potholes, ensuring your ride is stable and smooth.

Equipped with SRAM XX wireless transmission and Level Ultimate hydraulic brakes, allowing you to enjoy unparalleled handling and safety while pursuing speed, making every ride an unforgettable adventure! Below, we will analyze the downhill and uphill performance, main features, components, and specifications of Trek Top Fuel 9.9 XX AXS Gen 4, as well as other versions of the series.

Riding Experience

Since I own this Trek Top Fuel 9.9 XX AXS Gen 4, every ride feels like a deep conversation with nature, and every step is filled with strength and agility. Today, I would like to share with you an unforgettable riding experience and experience the outstanding performance of this bicycle in the mountains and forests. That morning, the sunlight shone through the gaps in the leaves, casting dappled shadows. I stepped onto my Top Fuel 9.9 XX AXS Gen 4, and the wheels gently rolled over the wet soil, making a rustling sound as I embarked on another exploration journey.

Climbing

At first, I walked along a winding path lined with lush trees, as if I were in a green tunnel. As the road conditions changed, I began to face a steep uphill slope. The terrain here has extremely high requirements for bicycles, but the Trek Top Fuel 9.9 XX AXS Gen 4 is fearless. I gently adjusted the gear, and the wireless transmission system responded quickly, with a smooth and precise shifting process.

Between pedals, the force is smoothly transmitted to the wheels, allowing me to easily tackle this challenge. Although the slope became steeper and steeper, my Top Fuel consistently maintained a stable output, allowing me to find joy in climbing.

Finally, I arrived at the mountaintop and my eyes suddenly opened up. A vast forest came into view, with sunlight shining on the treetops, shimmering with golden light. I paused for a moment, enjoying this rare tranquility and beauty. However, a more exciting journey is yet to come – I want to gallop down this winding downhill road.

Descending

When going downhill, the performance of the Trek Top Fuel 9.9 XX AXS Gen 4 amazed me even more. Its braking system – SRAM Level Ultimate 4-piston hydraulic brake, is responsive and powerful, allowing me to maintain calmness and control when facing steep and rugged roads. The RockShox Reverb AXS drop bar allows me to adjust my sitting posture at any time to cope with various road conditions in the best condition. And its 130mm RockShox Pike Ultimate fork and 120mm RockShox Deluxe Ultimate RCT rear bumper provide me with excellent shock absorption, even small potholes on the road cannot disturb my cycling rhythm.

I remember riding on an unrepaired forest trail. Although this path is picturesque, the road surface is covered with potholes and gravel, which greatly tests the skills of riders and the performance of bicycles. I move forward cautiously, always prepared to deal with possible emergencies. Just then, a sudden big pit appeared in front of me. I didn’t have time to react too much, so I had to rely on my trust in the Top Fuel 9.9 XX AXS Gen 4 and forcefully press the pedal, trying to overcome the obstacle. At that moment, I felt the powerful force emanating from the bicycle.

The OCLV Mountain Carbon frame demonstrated its toughness and lightness at critical moments. It did not deform or lose balance due to the sudden impact, but rather acted as a sturdy shield, protecting me from harm. At the same time, excellent shock absorption also played a key role at this time. They quickly absorbed the impact of the potholes, keeping the car stable and not losing control due to bumps.

Features

Adopting OCLV Carbon, it’s light yet strong. Mino Link allows 4-way geometry adjustment.

Equipped with 130mm Pike fork & 120mm RCT bumper for smooth riding. SRAM XX AXS system ensures precise shifting. SRAM Level brakes offer powerful stopping.

Reverb AXS drop bar adjusts seat height. Bontrager Line Pro wheels reduce weight. Design supports upgrades to 140mm fork, longer bumper, drop bar. BIT bag stores essentials.

Overall, Trek Top Fuel 9.9 XX AXS Gen 4 is a top-tier all-mountain bike, suitable for ultimate riding experiences.

Video

Other Versions

The Trek Top Fuel 9.7 is a high-end fully cushioned bicycle in terms of components, and compared to Trek’s latest Slash series, its price is still very friendly.

Trek Top Fuel 9.7

The lightweight and sturdy OCLV mountain all carbon fiber frame is equipped with Bontrager XR4 vacuum tire combination and Shimano transmission system, allowing you to enjoy a smooth riding experience. OX Performance Float shock absorbers and a longer 120mm rear travel can handle more challenging terrains. At the same time, the 4-piston Shimano brake can give you confidence even when going downhill. I think there is no better investment than owning an all-around champion bicycle. It will take you on a fun ride and provide you with the support you need for the race.

Benefits of the it

• 120mm rear suspension+130mm front suspension, providing a balanced riding experience.
• 4-way Mino Link geometry adjustment, easy storage with the BIT bag system.
• Upgrade friendly, with a 140mm front fork, long stroke shock absorption, and an extra long seat bar.

What we don’t like about it

• Slightly expensive price

FAQ

What are the new features of this framework compared to the previous generation?

-Carbon fiber and alloy frame reduce weight by approximately 220 grams

-The new 4-position Mino Link on the lower shock absorber bracket allows for adjustable geometry and leverage ratio

-Updated storage door with larger opening, better sealing, and equipped with new BITSbag system

-Improved dropper insertion

-Longer shock absorbers can be used to increase the rear travel to 130 millimeters (original factory 120 millimeters)

-The front fork has been approved to reach a maximum of 140 millimeters (original factory 130 millimeters)

-You can also use a 120mm front fork and lighter parts for a better XC feel

Is it compatible with other wheel/tire sizes?

yes. The front and rear wheels of the M-size and larger bicycles are both 29 inches, but 27.5-inch rear wheels can be installed in the “high” Mino position with a front fork travel of 140 millimeters. The front and rear wheels of the S bicycle are both 27.5 inches, providing riders with a more symmetrical riding experience and easier handling. These bicycles are not compatible with any other wheel size.

Does it have any framework storage, hidden tools, or other sophisticated accessories?

Say goodbye to the chloroprene rubber roll up style BIT bag. The Carbon Top Fuel model will include a brand new 2-bag BIT system, which has one bag that can be equipped with inner tubes and the other bag that can hold tools. The alloy model will be equipped with a new tool, the BIT package, but if you want to purchase the inner tube package separately, there is also enough space for the frame in the lower tube. The frame also has a larger opening, so you can easily put and take out the bag. If you want to store tools or inner tubes outside the lower tube, there is also a fitting installation point below the upper tube.

Size	Rider Height	Inseam
S	155 – 165 cm5’1″ – 5’5″	74 – 78 cm29″ – 31″
M	165 – 176 cm5’5″ – 5’9″	79 – 83 cm31″ – 33″
ML	173 – 180 cm5’8″ – 5’11”	81 – 86 cm32″ – 34″
L	177 – 188 cm5’10” – 6’2″	84 – 89 cm33″ – 35″
XL	188 – 195 cm6’2″ – 6’5″	89 – 91 cm35″ – 36″

Specs

Frameset

Frame	OCLV Mountain Carbon, internal storage, tapered head tube, internal guided routing, downtube guard, alloy rocker link, 4-way Mino Link, ABP, Boost148, 120mm travel
Fork	RockShox Pike Ultimate, DebonAir spring, Charger 3.1 RC2 damper, 44mm offset, Boost110, Maxle Stealth, 130mm travel
Shock	RockShox Deluxe Ultimate RCT, 185mm x 50mm
Max compatible fork travel	140mm

Wheels

*Wheel front	Size: S Bontrager Line Pro 30, OCLV Mountain Carbon, Tubeless Ready, 6-bolt, Boost110, 15mm thru axle, 27.5”
	Size: M, ML, L, XL Bontrager Line Pro 30, OCLV Mountain Carbon, Tubeless Ready, 6-bolt, Boost110, 15mm thru axle, 29”
*Wheel rear	Size: S Bontrager Line Pro 30, OCLV Mountain Carbon, Tubeless Ready, Rapid Drive 108, 6-bolt, SRAM XD driver, Boost148, 12mm thru axle, 27.5”
	Size: M, ML, L, XL Bontrager Line Pro 30, OCLV Mountain Carbon, Tubeless Ready, Rapid Drive 108, 6-bolt, SRAM XD driver, Boost148, 12mm thru axle, 29”
Skewer rear	Bontrager Switch thru axle, removable lever
*Tire	Size: S Bontrager Gunnison RSL XT, Tubeless Ready, triple compound, aramid bead, 120 tpi, 27.5×2.40”
	Size: M, ML, L, XL Bontrager Montrose RSL XT, Tubeless Ready, triple compound, aramid bead, 120 tpi, 29×2.40”
	Size: M, ML, L, XL Bontrager Gunnison RSL XT, Tubeless Ready, triple compound, aramid bead, 120 tpi, 29×2.40”
Tire part	Bontrager TLR sealant, 6oz
Max tire size	Frame: 29×2.50″, Fork: See manufacturer

E-system

Battery	SRAM eTap battery pack (with charger)

Drivetrain

Rear derailleur	SRAM XX SL Eagle AXS, T-Type
Crank	SRAM XX Eagle, DUB, 30T, T-Type, 55mm chainline, 170mm length
Bottom bracket	SRAM DUB MTB Wide, 73mm, BSA threaded
Cassette	SRAM Eagle XS-1299, T-Type, 10-52, 12 speed
Chain	SRAM XX Eagle, T-Type, 12 speed
Max chainring size	1x: 34T, min 30T

Components

Saddle	Verse Short Pro, carbon rails, 145mm width
*Seatpost	Size: S RockShox Reverb AXS, 100mm travel, wireless, 34.9mm, 340mm length
	Size: M, ML, L, XL RockShox Reverb AXS, 170mm travel, wireless, 34.9mm, 480mm length
*Handlebar/stem (integrated)	Size: S Bontrager RSL Integrated handlebar/stem, OCLV Carbon, 27.5mm handlebar rise, 820mm width, 0 degree stem rise, 35mm stem length
	Size: M, ML, L, XL Bontrager RSL Integrated handlebar/stem, OCLV Carbon, 27.5mm handlebar rise, 820mm width, 0 degree stem rise, 45mm stem length
*Brake	Size: S , M, ML, L, XL SRAM Level Ultimate 4-piston hydraulic disc
	Size: S , M, ML, L, XL SRAM Level Ultimate Stealth 4-piston hydraulic disc
Brake rotor	SRAM HS2, 6-bolt, 180mm
Rotor size	Max brake rotor sizes – Frame: 200mm, min 180mm, 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 300 pounds (136 kg).

Comparison table

Bicycle	Price	Frame material	Gear	Price
Trek Top Fuel 7	$3,529	Aluminum	1×12	Click View
Trek Top Fuel 8	$3,999	Aluminum	1×12	Click View
Trek Top Fuel 9.7	$4,499	Carbon	1 × 12	Click View
Trek Top Fuel 9.8 XT	$7199	Carbon	1×12	Click View

Comparison

Trek Top Fuel 9.9 XX AXS Gen 4 VS Top Fuel 7

The Trek Top Fuel 9.9 XX AXS Gen 4 features a high-end OCLV Mountain Carbon frame, equipped with SRAM XX AXS wireless transmission system, RockShox Pike Ultimate front fork, and Deluxe Ultimate RCT rear bumper, providing high-quality suspension with 130mm front stroke and 120mm rear stroke, suitable for riders who pursue ultimate lightweight and excellent performance. In contrast, the Trek Top Fuel 7 adopts an aluminum alloy frame, which is more affordable in price. However, its RockShox 35 Gold RL front fork and Fox Performance Float DPS rear bumper configuration, as well as a 120mm front and rear suspension travel, can also provide stable handling and comfortable riding experience, suitable for ordinary riders. In short, the Top Fuel 9.9 XX AXS Gen 4 features a lighter design and more advanced configuration, suitable for professional or high-end needs, while the Top Fuel 7 is widely welcomed for its practicality and cost-effectiveness.

Learn More：https://bestbikeselect.com/trek-top-fuel-7-review/

Trek Top Fuel 9.9 XX AXS Gen 4 VS Top Fuel 8

The Top Fuel 8 features a lightweight aluminum alloy frame , providing a 120mm shock absorption travel, suitable for riders who pursue cost-effectiveness and stability.

The Top Fuel 9.9 XX AXS Gen 4 adopts a more advanced OCLV Mountain Carbon frame, paired with RockShox Pike Ultimate front fork , providing higher rigidity and smoother shifting experience. It also has 130mm front suspension and 120mm rear suspension, suitable for riders who pursue ultimate performance and handling experience.

Learn More：https://bestbikeselect.com/2022-trek-top-fuel-8-review/

Trek Top Fuel 9.9 XX AXS Gen 4 VS Trek Top Fuel 9.7

The Top Fuel 9.7 is made of OCLV all carbon fiber material, equipped with a 120mm front and rear travel suspension system and Shimano XT M8100 12 speed transmission system, suitable for endurance cycling and handling rough terrain.

The Top Fuel 9.9 XX AXS Gen 4 adopts a more high-end carbon fiber material, equipped with a 130mm front suspension and a 120mm rear suspension, as well as an ultra light SRAM XX AXS wireless transmission system, and is equipped with a 4-way Mino Link lower suspension mounting seat, providing riders with more precise geometric adjustments and suspension feel control, making it the first choice for pursuing the ultimate all mountain carbon fiber riding experience.

Learn More：https://bestbikeselect.com/2023-trek-top-fuel-9-7-review/

Trek Top Fuel 9.9 XX AXS Gen 4 VS Trek Top Fuel 9.8 XT

Top Fuel 9.8 XT uses OCLV Carbon, lightweight and strong. It features Shimano XT 1×12 gears and Bontrager 30 tires for stability and shock absorption.

Top Fuel 9.9 XX AXS Gen 4 focuses on high-end specs. It has carbon frame and wheels, SRAM XX wireless gears for precise shifting. The 4-way Mino Link allows personalized geometry and shock absorption adjustments.

Learn More：https://bestbikeselect.com/2023-trek-top-fuel-9-8-xt-review/

Final Verdict

When pursuing the ultimate all mountain carbon fiber cycling experience, the Top Fuel 9.9 XX AXS Gen 4 is undoubtedly the first choice. It provides unparalleled handling and flexibility for riders with its ultra light frame, carbon fiber wheels, and SRAM XX wireless transmission system. The RockShox Ultimate with 120mm rear suspension and 130mm front suspension provides a balanced and comfortable ride, showcasing excellent performance on both rugged uphill and cheerful downhill slopes. And its unique 4-way Mino Link design allows riders to easily adjust the geometry and suspension feel according to their personal preferences and riding needs. In short, the Top Fuel 9.9 XX AXS Gen 4 not only represents the pinnacle of Trek Bikes in the field of bicycle manufacturing, but also the dream choice for every seeker of a top mountain riding experience.