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  • Niner - Air 9 RDO Mountain Bike Frame - 2017 - Black/Red
  • Niner - Air 9 RDO Mountain Bike Frame - 2017 - CMYK
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  • Niner - Air 9 RDO Mountain Bike Frame - 2017 - Black/Red
  • Niner - Air 9 RDO Mountain Bike Frame - 2017 - CMYK

Niner Air 9 RDO Mountain Bike Frame - 2017


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    3 Reviews


    Catch air.

    While we've been known to rip some gnarly trails on a cyclocross rig and bask in the adrenaline rush of simply surviving with life and limb intact, we'll readily admit that sometimes a little bit of squish would make the ride a lot bit better. For those of us that love to ride fast and revel in the challenge of nimbly picking through technical, rocky sections that full suspension whips plow indiscriminately through, Niner drops the 2017 Air 9 RDO Mountain Bike Frame. With a Boosted rear axle spacing and tweaked geometry, this hardtail is ready to shred.

    The most notable changes include a lower handlebar height, giving the Air 9 a nudge towards the venerable RKT 9 RDO's aggressive positioning. Paired with a longer cockpit and slacker head tube, this makes for a frame that handles deftly on knife-edge lines and jumps the second you need it to. Compared to the previous Air 9 the chainstays scrunched in by 4mm to 435mm for lightning fast acceleration and nimble handing without crossing over into jumpy, squirrely territory.

    The new Air 9 RDO also sizes down its seatpost diameter to 27.2mm to take advantage of that little bit of extra flex and resulting comfort found in a narrower post. Out back, this year's model now boasts another different dimension; namely, a 12 x 148mm Boost axle width, keeping it in line with current trends for wider hubs and stiffer wheelsets. Niner also tucks the brake caliper mounts on the chainstay, neatly within the rear triangle. This makes sense from a frame building standpoint, as the seatstay is generally the burlier of the two rear stays and the placement protects the caliper somewhat in the event of a crash. We also think that particular placement just plain looks better than an ungainly bump hovering above a seatstay.

    As with Niner's other RDO offerings, the Air 9 RDO is constructed using Niner's Carbon Compaction System (CCS), which gives Niner complete control over tube wall thickness across the frame. This makes for tube walls that are virtually perfect, reduces the amount of materials required, and eliminates excess resin build-up. The result is a claimed weight loss of 10%, which is a nearly unheard of leap between model years.

    The Air 9 RDO’s large bottom bracket area provides stiff, efficient power transfer and sure handling, with the added bonus of versatility when choosing your bottom bracket. Opt for the standard PF30 on a geared setup, or swap it out for Niner's separately sold BioCentric 30 bottom bracket cups to go singlespeed or for compatibility with your favorite 24mm spindle cranks.

    The 2017 Niner Air 9 RDO Mountain Bike Frame is designed to pair with a 100mm travel fork for race-worthy, aggressive positioning or a 120mm fork for more upright, all-day trail fun.

    • Item #NNR004X

    Tech Specs

    Frame Material
    carbon fiber
    Wheel Size
    29 in
    Fork Travel
    [recommended] 100 - 120 mm
    Head Tube Diameter
    1-1/2 to 1-1/8in tapered
    Headset Included
    yes, Cane Creek 40
    Bottom Bracket Type
    73 mm PressFit 30
    ISCG Tabs
    Cable Routing
    Front Derailleur Mount
    34.9 high clamp
    Derailleur Pull
    bottom, side
    Brake Type
    Seatpost Diameter
    27.2 mm
    Seat Collar
    31.8 mm
    Rear Axle
    12 x 148mm Boost
    Recommended Use
    cross country
    Manufacturer Warranty
    5 years

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Smooth rider

    • Familiarity: I've used it once or twice and have initial impressions

    I picked up this bike a few weeks ago and was finally able to hit the trails yesterday, and all I can say is wow! The Fox Float fork, Niner carbon wheels and Sram X01 Eagle performed flaslessly.
    I have not ridden a hardtail in years, and this bike blew me away at how well it handled rough terrain. The bike was stable on the steepest of descents and climbed like a goat.
    I'd be happy to assist you with your custom build or answer any questions you may have.

    Dangerously Fast

    • Familiarity: I've put it through the wringer

    Replaced a 9 year old Air 9 Aluminum. Upgraded to RDO, Industry Nine wheel set and XT brakes. This frame is great for climbing and if you are coming from aluminum it rides softer and holds a line better on the downhill. I love it.
    Just wish Niner had included a chain suck guard. Seems cheap of them not to.

    New and Improved!

      One of my favorite hardtails we offer. The new version of this bike features boost spacing making the bike very laterally stiff which equates to incredible power transfers. Its a very fast and efficient ride and highly recommended!
      If you need help configuring this frame or have quesions with it or the new boost spacing feel free to reach out to me direct.
      Wes Branham- Account Manager -Bike

      I will check with Niner on the frame weight for you. We can spec the bike with a 100mm fork as well. Send me an email on how you would want the bike spec'd and I will shoot you over a quote.

      Does anyone know the max 27.5 tire size that will fit on this frame?

      Hey Justin,

      Niner does not put a max tire width spec on this bike. On their regular builds they have their Niner Carbon XC wheels which have a 24mm internal width with a 2.2 inch Maxxis Ikon on the rear. That will give you a good starting point, If you want to reach out to me, I can contact Niner directly to give you a full answer.

      You can reach me at

      what is the weight in grams of the Air 9 RDO frame? (Why is it not posted if it's so light?)

      Hey Matthew - These Air 9 RDO frames weigh approximately 1,050 grams with hardware (seat collar and derailleur hanger, plus paint and protective tape). Feel free to contact me directly with any additional questions, especially if you are interested in ordering this frame or building a complete bike.

      - Kyle L. - Expert Gearhead - - 801-736-4337