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Dominate the podium.

With so many rider's turning to full suspension bikes to explore trails, is there any place for the hardtail? Niner answers with a resounding yes, as its A.I.R. 9 is one of the most podium dominating, versatile steeds in the industry. The A.I.R. 9 is the product of the American based company who answers to feedback, not just from pros but from everyman riders who are passionate about the 29er platform. And they rely upon testing the prototypes themselves for real world, on-the-fly feedback as well.

Finite Element Analysis is the core of the A.I.R. 9's success. This method of analysis involves the mathematically based finite element method which calculates component displacements, strains, and stresses under internal and external loads. By developing a computer model of the frame, Niner's engineers are able to optimize the structure and layup of the carbon fiber to provide strength and durability throughout the frame. Additionally, FEA allows designers to look at the effects of various tube shapes on the durability as well as the performance of the frame. The result is a somewhat unconventional form with a curved top tube and fluid joints that was designed to damped chatter and to move impact to stronger parts of the frame, thus increasing durability. A reinforced bottom bracket shell and oversized chainstays mean that while power goes directly to your rear wheel, right where you want it, chatter from rough trails isn't translated to the rider because it is absorbed by the curved seatstays.

Niner used its Bio-Centric EBB technology and CYA Bottom Bracket in the A.I.R. 9 frame. Rather than having to rely upon just one standard or option in crankset and gearing, using a series of press-fit inserts, which are sold separately, the Shimano or SRAM BB30, BB92, or standard external cups may be used. And, it's easy to switch from gears to single-speed when you want to get a bang for every workout late in the season. Additionally, the EBB means that as a single speed build, you won't have to deal with chain tension issues.

If you're concerned about the maintenance issues and constant creaking that seem to haunt eccentric bottom brackets, you'll be pleased that Niner locks the cups to the bottom bracket shell's flange. This design means that dust and debris is not able to lodge itself into the interface between the frame and the cups.

The Niner rides smoothly with either a rigid or suspension fork. The award-winning Niner fork features a 470mm axle to crown length and 45mm offset and that is what they recommend for any rigid for you may wish to add. If you want to maximize the potential of the bike, choose an 80-100mm suspension fork. The tapered head tube comes with an FSA IS42/28.6/IS52/40 integrated headset. The frame fites a 31.6mm seatpost. If you choose to run a double or triple crankset in the front, you'll need a high-mount, botto-swing, buttom-pull front derailleur with a 34.9mm clamp. It fits rotors up to 160mm and the rear triangle provides enough clearance for 2.4inch tires. Maximum chainring size is 26/39t SRAM or 28/40t Shimano XT. XTR is not compatible for 2 x 10 due to interference. All triple cranksets are compatible. For a one-by drivetrain, such as SRAM's XX1, the AIR 9 Carbon will clear up to a 32t ring with a 168mm Q-Factor crankset.

As the frame comes set up for singlespeed only, Niner's geared kit is sold separately (NNR0024). The Niner A.I.R. 9 Carbon Mountain Bike Frame - 2013 is available four sizes from Small to X-Large and in the colors Black, White, and Tangerine.

  • Reviews
  • Q & A

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No Gravity on the Moon

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

Built this frameset up as a single speed as a simple trail steed. Impressed that the geo fits nicely between XC and All mounting, giving you performance in climbing, while still having a slack enough head tube to make it fun rallying down the trail. The Moondust finish looks great, as does the build quality. The only complaint I have is that Niner does not include/offer block offs for the internal frame routing, so if you do not use it, your left with open holes.


    mediums are sold out as of 5/12. We do have one small left. We could also do the same build on a 2014 frameset still at an amazing value. Contact me direct for details at or 801-736-6396 x 4074

    Great frame

    • Familiarity: I've used it several times

    Got this frame 2 months ago. Running 1x10 w/xt shadow plus rear, xt cranks & raceface chainring. xt brakes w/icetech rotors, rockshox reba rl w/remote, Thompson x4 stem w/truvativ noir carbon bars & seatpost w/wtb rocket comp saddle, continental xc kings tubeless on wtb i23 wheelset w/ xt hubs. love this bike, very snappy, handles great. very light. love climbing with this bike. highly recommend this frame.

    update: btw this raceface chainring is no joke. haven't dropped the chain once in about 20 rides.

    A work of art...

    • Familiarity: I've put it through the wringer

    I've owned one of these for about a year and set it up with an all RDO cockpit and an XX1 drivetrain. It is an amazing bike: light, snappy, nimble in the air, and a fast climber. I love this on long climbs, but you do have to pick your lines carefully downhill on technical descents with a 100mm course. It is, after all, and XC bike, but rides more capable than that. Love it.

    Stiff and responsive

    • Familiarity: I've used it several times

    Only got a few days in on this bike, but what really stood out was the stiffness and agility. I like to focus on the downs, and didn't have the highest expectations for this bike, but it really delivered a balanced trail experience, and not just a light weight frame for the carbonerds


      Great idea but not the best for racing. I converted this bike to geared and it made a ton of BB noise. If you want to run gears get the RDO but if you want two bikes for the price of 1.5 then this is your frame.


      Really fun bike!

      • Familiarity: I've put it through the wringer

      I bought the A.I.R. 9 in August (size Small) and cobbled together as a SS: 32x20T drivetrain (EThirteen guidering/Surly cog), Fox Float CTD fork (100mm travel), Shimano XT brakes, Shimano XT crank set (revived for this purpose), XT hubs laced to WTB rims (TL), SRAM 9 speed chain, Easton EA70 stem, Niner carbon bars/seat post, Selle Italia saddle, ESI chunky grips, XTR pedals and finally GEAX Saguaro tires.

      I'd not previously ridden a carbon bike (other than my road bike) so I was really psyched the first time I took it on the trail. Very stiff (climbing), responsive handling (cornering), and overall comfortable in the saddle. At 5'-7"ish, the fit on the size small was spot on (saddle a touch forward from center with a 90mm stem). The carbon bits (bar/seat post) made riding in the saddle a pleasure.

      Are you planning on getting another shipment...

      Are you planning on getting another shipment on the large frames like you did in late march?

      Hey Jeff, unfortunately we won't be gettin in more of those in in the Large size as they are no longer available. We do have the 2014 version in stock though. Please let us know if you have any other questions on those. You can reach me directly at 801 736 6396 ext 4362

      Are the Medium frames all gone?

      Are the Medium frames all gone?

      Does the Medium frame have mounts for 2...

      Does the Medium frame have mounts for 2 water bottles?

      Trevor, I believe in this particular frame, all sizes have two bottle mounts. The small and medium frames both have one mount inside the triangle and one on the bottom of the downtube. The large and XL have both mounts inside the triangle. My only gripe about this frame as mediums normally have both inside.

      Any word on availability of the size M...

      Any word on availability of the size M Moondust?

      Can I get size L??(color : Tangerine)

      Can I get size L??(color : Tangerine)

      Does this come with the EBB cups, or do...

      Does this come with the EBB cups, or do they need to be purchased like the other BB inserts?

      Best Answer

      Does NOT come with an EBB, or any other type of BB adaptor system. It does have a singlespeed specific dropout installed. You'll have to order the EBB or CYA you want, as well as a derailleur hanger if you wish to run gears. I mentioned that the description is lacking this sort of info, and how it kind of sucks to be the customer, all amped on your new ride, only to find you need to throw it in a corner and order more parts, when it arrives as it does. Guess that fell on deaf ears.

      can you put a 140mm fork on it ?

      can you put a 140mm fork on it ?

      Niner recommends an 80 to 100mm suspension fork, or a rigid unit with a 470mm axle to crown length and 45mm offset. Sorry to say that a 140mm fork would not be advised for this frame at all. Pretty much the tallest fork that would be recommended on a hardtail 29er is a 120mm fork on such bikes like the Merlin XLM, Santa Cruz Highball, and Pivot Les.

      I know that for most part, the Niners come...

      I know that for most part, the Niners come with a headset, and for awhile, they came with two headset crown races. One was typical for a tapered steerer fork, and he other allowed the use of a straight 1-1/8" steerer. Can you tell me if this frame comes with both options? I'll be running a straight steerer at first, and need to know if I need to be ordering the other race from the Niner site.