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Session 9.9 29

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 that 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, 190 mm 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 racing bike, and it's built so you can refine your set-up for your fastest runs with Mino Link and has 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.

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 dialled set-up: 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 your personal handling requirements



  • Frameset

    OCLV Mountain Carbon main frame and stays, ABP, magnesium EVO Link, tapered head tube, Mino Link, integrated frame protection, Control Freak internal routing, Carbon Armor, ISCG mount, 190 mm travel
    Fox Factory 40 FIT Grip2, air spring, Kashima Coat, hi/lo speed compression, Boost 110x20 thru axle, 190 mm travel
    Rear suspension
    Fox Factory Float X2, high/low speed rebound adjust, high/low speed compression adjust, tuned by Trek Suspension Lab, 225x70 mm
  • 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, 83 mm
    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, 31.6 mm, 0 mm offset
    Bontrager Line Pro, OCLV Carbon, 35 mm, 15 mm rise, 820 mm width
    Bontrager XR Trail Elite, alloy lock-on
    Bontrager Line Pro Direct Mount, 35 mm clamp, 50 mm length
    Head set
    FSA Orbit, sealed cartridge bearing, 1-1/8" top, 1.5" bottom (includes geometry-adjust angled cups)
    Brake set
    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 136 kg (300 lb).
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 on Trek pre-production painted frames at the time of publication. Weights may vary in final production.

Sizing & fit

Proper bike fit is essential for best performance and comfort. Any size and geometry measurements shown on trekbikes.com are for general comparison purposes only. To find your perfect fit, visit an authorised Trek retailer, where an expert skilled at sizing will help you find the appropriate bike and size for your individual needs.


Rider Height


All measurements provided in cm unless otherwise stated.

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
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
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
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
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
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
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
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
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

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