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 130mm front and 120mm rear travel for ripping over rocks and roots without sacrificing power on ascents. Its built from lightweight Alpha Platinum Aluminum 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.
- Its lightweight frame and versatile geometry make it the perfect choice for all kinds of rides and all kinds of riders
- The 4-way Mino Link makes it easy to adjust your geometry or leverage rate for how and where you want to ride
- You get a sweet balance of price and performance with upgraded components and a rugged alloy frame
- The Alpha Platinum Aluminum frame is robust, yet light, and packs in updated internal frame storage for easy access to gear and snacks
- Its more upgrade-ready than ever, with room for bigger 140mm forks and longer-stroke shocks for up to 130mm of rear travel, plus room for extra-long dropper posts
Make Top Fuel yours
Opt for light parts and a 120mm fork for a featherweight Top Fuel, or a 140mm fork and longer-stroke 130mm rear shock for extra versatility. Room for a longer dropper and MX wheels lets you customize Top Fuel into an ultimate playful trail whip.
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4-way Mino Link
Easily adjust the suspension and geometry four different ways for where and how you ride. With the flip of a chip, you can ride with more or less progressive suspension, and tweak your geometry for a slacker head tube and lower BB or steeper head tube and higher BB.
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New internal storage with new BITS bags
New internal frame storage bags make it easy to ditch the pack and still carry your ride essentials.
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Active Braking Pivot
Active Braking Pivot allows our engineers to tune how the suspension reacts to acceleration and braking forces independently. That means you get more confident control when you need it most.
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Shimano XT
Shimano XT is the original mountain bike groupset and trusted by generations of mountain bikers around the world. Whatever the trail, wherever you ride, XT is your solution for mountain biking today. Reliable shifting. Superior braking. Intuitive maintenance. XT is the high performance workhorse you can count on.
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| Frame |
Alpha Platinum Aluminum, internal storage, tapered head tube, internal guided routing, downtube guard, alloy rocker link, 4-way Mino Link, ABP, Boost148, 120mm travel |
| Fork |
Fox Rhythm 34, Float EVOL air spring, GRIP damper, tapered steerer, 44mm offset, Boost110, 15mm Kabolt axle, 130mm travel |
| Shock |
Fox Performance Float DPS, 2-position damper, 185mm x 50mm |
| Wheel Front |
Bontrager Line Comp 30, Tubeless Ready, 6-bolt, Boost110, 15mm thru axle, 27.5 / |
| Wheel Rear |
Bontrager Line Comp 30, High Strength 6000 Series Aluminum rim, Tubeless Ready, Rapid Drive 108, 6-bolt, Shimano MicroSpline freehub, Boost148, 12mm thru axle, 27.5 |
| Tire |
Bontrager Gunnison Pro XR, Tubeless Ready, wire bead, 60 tpi, 27.5x2.40 |
| Tire Part |
Bontrager TLR sealant, 6oz |
| Skewer Rear |
Bontrager Switch thru axle, removable lever |
| Shifter |
Shimano XT M8100, 12 speed |
| Rear Derailleur |
Shimano XT M8100, long cage |
| Crank |
Shimano Deore M6120, 30T ring, 55mm chainline, 170mm length |
| Bottom Bracket |
Shimano BB-MT501 BSA |
| Cassette |
Shimano SLX M7100, 10-51T, 12 speed |
| Chain |
Shimano SLX M7100, 12 speed |
| Brake |
Shimano 4-piston hydraulic disc, M6100 lever, M6120 caliper // Shimano 4-piston hydraulic disc, M6100 lever, M6120 caliper |
| Brake Rotor |
Shimano RT66, 6-bolt, 180mm |
| Saddle |
Bontrager Verse P3, chromoly rails |
| Seatpost |
Bontrager Line Dropper, 100mm travel, MaxFlow, internal routing, 34.9mm, 310mm length |
| Handlebar |
Bontrager Line, alloy, 35mm, 27.5mm rise, 780mm width |
| Stem |
Bontrager Elite, 35mm, 0 degree, 45mm length |
| Grips |
Bontrager XR Trail Comp, nylon lock-on |
Geometry Chart
| B B Drop |
1 |
| Chainstay Length |
43.4 |
| Eff Seat Tube Angle |
76.5° |
| Eff Top Tube |
55.8 |
| Frame Reach |
42.2 |
| Frame Size Letter |
S |
| Frame Stack |
56.6 |
| Head Angle |
65.9° |
| Head Tube Length |
10.5 |
| Offset |
4.3 |
| Position |
High |
| Seat Tube |
36 |
| Seat Tube Angle |
69.5° |
| Standover |
70.5 |
| Trail |
11.1 |
| Wheelbase |
115 |
| Wheel Size |
27.5" |
| B B Drop |
2.6 |
| Chainstay Length |
43.4 |
| Eff Seat Tube Angle |
77.3° |
| Eff Top Tube |
58.7 |
| Frame Reach |
45.2 |
| Frame Size Letter |
M |
| Frame Stack |
59.9 |
| Head Angle |
65.9° |
| Head Tube Length |
10.5 |
| Offset |
4.3 |
| Position |
High |
| Seat Tube |
41 |
| Seat Tube Angle |
70.5° |
| Standover |
75.5 |
| Trail |
12.1 |
| Wheelbase |
118.8 |
| Wheel Size |
29" |
| B B Drop |
2.6 |
| Chainstay Length |
43.9 |
| Eff Seat Tube Angle |
76.6° |
| Eff Top Tube |
61.1 |
| Frame Reach |
46.7 |
| Frame Size Letter |
ML |
| Frame Stack |
60.4 |
| Head Angle |
65.9° |
| Head Tube Length |
11 |
| Offset |
4.3 |
| Position |
High |
| Seat Tube |
42 |
| Seat Tube Angle |
70.5° |
| Standover |
75.5 |
| Trail |
12.1 |
| Wheelbase |
121 |
| Wheel Size |
29" |
| B B Drop |
2.6 |
| Chainstay Length |
43.9 |
| Eff Seat Tube Angle |
76.3° |
| Eff Top Tube |
63 |
| Frame Reach |
48.2 |
| Frame Size Letter |
L |
| Frame Stack |
60.8 |
| Head Angle |
65.9° |
| Head Tube Length |
11.5 |
| Offset |
4.3 |
| Position |
High |
| Seat Tube |
43.5 |
| Seat Tube Angle |
70.5° |
| Standover |
76 |
| Trail |
12.1 |
| Wheelbase |
122.7 |
| Wheel Size |
29" |
| B B Drop |
2.6 |
| Chainstay Length |
44.4 |
| Eff Seat Tube Angle |
75.6° |
| Eff Top Tube |
67.2 |
| Frame Reach |
51.2 |
| Frame Size Letter |
XL |
| Frame Stack |
62.6 |
| Head Angle |
65.9° |
| Head Tube Length |
13.5 |
| Offset |
4.3 |
| Position |
High |
| Seat Tube |
47 |
| Seat Tube Angle |
70.5° |
| Standover |
76.5 |
| Trail |
12.1 |
| Wheelbase |
127 |
| Wheel Size |
29" |
