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SALE 2019

Session 9.9 29

$6,699.99 $8,399.99 Model 24584

Session 9.9 is the pinnacle of downhill mountain bike performance. It's built for one reason: going as fast as freakin' possible down hills. It pairs proven Shimano Saint parts with our premium OCLV Mountain Carbon frame and FOX Factory suspension with super-fast 29" wheels. This is the same DH bike the pros ride, and the bike of choice for World Champion Gee Atherton.

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It's right for you if...

You want the fastest downhill bike we offer. You want the speed of 29˝ wheels and the stability of a full-on DH frame. You seek out the fastest lines, and the biggest jumps. You like to dial in your ride, and want the ability to fine-tune your suspension, fit, and handling on a bike that makes no compromises.

The tech you get

An OCLV Mountain Carbon frame, 190mm tunable front and rear FOX Factory air suspension, Bontrager Line DH wheels, and proven Shimano Saint drivetrain and brakes. This is a full-on DH race bike, and it's built so you can refine your setup for your fastest runs with Mino Link and an adjustable fixed-angle headset.

The final word

Best frame, best suspension, best parts, and fast-rolling 29˝ wheels. This is the only choice if you're a true DH devotee. Session 9.9 is simply the fastest bike on the mountain, even when that mountain is a stop on the World Cup circuit.

See it in action

favorite_borderWhy you'll love it

  1. It's like a precision wrecking ball that gives you the confidence to tear down mountains and take the fastest, burliest lines
  2. The fastest runs demand the most dialed setup: the air shock and fork on Session 9.9 are adjustable and easy to fine-tune for different tracks
  3. Mino Link and fixed-angle headset cups let you adjust your geometry for the exact handling you want

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OCLV Mountain Carbon

Trek's mountain-specific carbon fiber is tougher carbon, with unique materials and layup procedures, Trek's advanced engineering, and a higher standard of testing.

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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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  • Frameset

    OCLV Mountain Carbon main frame & stays, ABP, magnesium EVO Link, tapered head tube, Mino Link, integrated frame protection, Control Freak internal routing, Carbon Armor, ISCG mount, 190mm travel
    Fox Factory 40 FIT Grip2, air spring, Kashima Coat, hi/lo speed compression, Boost 110x20 thru axle, 190mm travel
    Rear suspension
    Fox Factory Float X2, high/low speed rebound adjust, high/low speed compression adjust, tuned by Trek Suspension Lab, 225x70mm
  • Wheels

    Bontrager Line DH 30, Tubeless Ready, Boost 110x20 front, 157x12 rear w/7 speed DH freehub
    Bontrager G5 Team Issue, wire bead, 29x2.50˝
  • Drivetrain

    Shimano Saint, 10 speed
    Rear derailleur
    Shimano Saint M820, Shadow Plus
    Shimano Saint M825, 36T w/MRP G4 carbon chainguide
    Bottom bracket
    Shimano SM-BB80, 83mm
    Shimano CS-5700, 11-25, 10 speed
    KMC X10
    Wellgo MG-1, magnesium body, Cro-Mo axle, replaceable pins
  • Components

    Bontrager Arvada, austenite rails
    Bontrager Rhythm Elite, 31.6mm, 0mm offset
    Bontrager Line Pro, OCLV Carbon, 35mm, 15mm rise, 820mm width
    Bontrager XR Trail Elite, alloy lock-on
    Bontrager Line Pro Direct Mount, 35mm clamp, 50mm length
    FSA Orbit, sealed cartridge bearing, 1-1/8˝ top, 1.5˝ bottom (includes geometry adjust angled cups)
    Shimano Saint M820 hydraulic disc
  • Weight

    M - 15.65 kg / 34.5 lbs (with tubes)
    Weight limit
    This bike has a maximum total weight limit (combined weight of bicycle, rider, and cargo) of 300 pounds (136 kg).
We reserve the right to make changes to the product information contained on this site at any time without notice, including with respect to equipment, specifications, models, colors, and materials.
Bike and frame weights are based off Trek pre-production painted frames at time of publication. Weights may vary in final production.

Sizing & fit

The charts below show our recommended sizes based on height, but there are some other factors, like arm and leg length, that determine a great fit. That’s why you’ll see some overlap in our recommendations. Not every rider who’s 5´8˝, for example, will fit on the same size bike. The best way to find your perfect fit is to consult the experts at your local Trek retailer.


Rider Height


All measurements provided in cm unless otherwise noted.

Frame size letter Geometry position Wheel size A — Seat tube B — Seat tube angle C — Head tube length D — Head angle E — Effective top tube F — Bottom bracket height G — Bottom bracket drop H — Chainstay length I — Offset J — Trail K — Wheelbase L — Standover M — Frame reach N — Frame stack
S High 29" 42.5 57.0° 11.5 62.6° 56.8 35.6 1.6 45.2 5.8 12.8 122.8 74.1 40.0 61.6
M High 29" 42.5 57.0° 11.5 62.6° 58.7 35.6 1.6 45.2 5.8 12.8 124.7 74.2 42.0 61.6
L High 29" 45.6 57.0° 11.5 62.6° 60.8 35.6 1.6 45.2 5.8 12.8 126.8 74.7 44.0 61.6
XL High 29" 45.6 57.0° 11.5 62.6° 63.3 35.6 1.6 45.2 5.8 12.8 129.3 74.9 46.5 61.6
S Low 29" 42.5 56.6° 11.5 62.1° 58.3 35.0 2.3 45.3 5.8 13.1 122.6 73.5 39.6 61.9
M Low 29" 42.5 56.6° 11.5 62.1° 60.2 35.0 2.3 45.3 5.8 13.1 124.5 73.6 41.5 61.9
L Low 29" 45.6 56.6° 11.5 62.1° 62.3 35.0 2.3 45.3 5.8 13.1 126.6 74.3 43.6 61.9
XL Low 29" 45.6 56.6° 11.5 62.1° 64.8 35.0 2.3 45.3 5.8 13.1 129.1 74.5 46.1 61.9

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