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Niner AIR 9 & AIR 9 RDO Review

Review Of Niner Air 9The Niner Air 9 and Air 9 RDO are two of the most distinctive mountain bikes from Niner’s collection.

RATING: Great value!
BEST FOR: Suitable for beginners, average riders, and pros — anyone can have fun on them and improve their results.
FEATURES: Quality Niner frame, 27.5 or 29″ wheels, 1×12 SRAM drivetrain, SRAM hydraulic disc brakes

Full Specs

See below:

Air 9

Air 9 RDO

Sizes & Buying Options

XS – 5’0” – 5’5″
S – 5’3″ – 5’9″
M – 5’8″ – 6’0″
L – 5’11” – 6’3″
XL – 6’3″ – 6’7″

Check availability – JensonUSA



  • Highly reliable and affordable
  • Quality SRAM components
  • Suitable for different types of riders
  • Plenty of clearance for wide tires


  • Top models are pricey

Full Review

See On JensonUSA

Since a couple of years ago, the Niner Air 9 and Air 9 RDO are back on the Niner’s list of masterpieces, after a long hiatus. They keep improving them regularly, offering fresh builds, improvements in geometry, and new attractive paint jobs.

One of the benefits of these and other Niner bikes is that you are not confined to a single choice when it comes to components. You can choose to make your new 29er as expensive and capable as you wish, or you can make compromises and save some money in your pocket.

The Niner Air 9 and Air 9 RDO are two of the most distinctive mountain bikes from Niner’s collection, in our opinion. We think so because they are suitable for beginners, average riders, and pros — anyone can have fun on them and improve their results.

Let’s take a closer look at what these bikes are and who they are made for!

Niner Air 9 And Air 9 RDO: Who Are They For?

Niner Air 9 and Air 9 RDO are two fast and capable hardtail bikes made by the famous American bike brand. They are considered by many to be the perfect marriage between XC and Trail bikes, which makes them incredibly versatile.

If you are on the lookout for a nimble and quick bike, that does well both in corners and on straights, one of these could be your best choice.

Niner bike riding

Patrick Durkin Cummins: UFC Fighter on a Niner

The Air 9 is the more affordable choice, intended for XC and Trail enthusiasts, who do not plan to enter any pro races, but are just looking to spend as much time in nature as possible and have as much fun as possible on rides and in amateur events.

On the other hand, the Niner Air 9 RDO is a race-ready machine with a slightly different geometry than the Air 9. With the right pair of legs on its pedals, it can win any competition that it finds itself in.

In the next section, we’ll tell you everything you need to know about the best features of both models and take a closer look at the available builds. After that, you can make a better choice for your trail adventures.

Air 9 Highlights

Niner Air 9 is a reasonably-priced aluminum XC/Trail bike that brings this MTB category to the average rider. As Niner say themselves, if an XC race bike met a Trail bike in the woods and they fell in love, Air 9 would be their child. This observation makes a lot of sense when you look at the geometry and the components that you get on this model.

Niner Air 9

First of all, they tried and tested hydroformed aluminum frame is light enough and stiff enough to start flying when you stomp on the pedals. The famous Niner’s Revolution Geometry puts the rider in the most balanced riding position for downhills, uphills, straights, and corners.

The head tube angle is 68 degrees, whereas the seat tube angle is 74 degrees. Therefore, you will be positioned just above the bottom bracket which will maximize your pedaling efficiency. Moreover, the slack HT angle will give you more control and stability on challenging portions of the trail.

Niner Air 9 is also incredibly versatile thanks to the Boost 148 spacing, which lets you go with either 27.5×3.0″ or 29×2.4″ tires. Niner stands firmly behind their recognizable 29ers, but they are not bling to the benefits of smaller wheels as well.

See the Selection on – JensonUSA



2-Star NX Eagle 29

As we mentioned, Niner bikes come with different builds, which represent different components and groupsets but the same, perfected frame. Its price starts at around $1,500 and caps at around $1,950, depending on the version you choose.


This 2-Star NX Eagle build has a RockShox Judy Gold RL Solo Air fork that boasts 120 mm of smooth and responsive travel. In combination with the slack head tube angle, it will allow you to hit any oversized bumps hard. Moreover, it comes with Maxxis tires that are 2.5/2.4″ wide for maximum stability.

This build sports a 1×12 SRAM NX Eagle drivetrain, with a compatible derailleur and crankset. The cassette offers a wide range of gears with a 10-50 ratio, so the hills will stand no chance.

When you get to the top of the hill and decide to storm down, you can control your speed with a pair of SRAM Level hydraulic disc brakes with massive 180/160 mm rotors.

The total weight of this build is 28.3 lbs, which is on the high side, but it’s a fantastic choice for a trail and XC enthusiast who cares about personal records and not about winning high-profile races.

2-Star NX Eagle 27.5

Interestingly, Niner has a 27.5″ build available as well.

Niner Air 9 2-Star NX Eagle 27+

All of the components are the same as with the 29″ build we described above, but the tires are 27.5″ in diameter. Of course, the tires are different as well. This Air 9 has a pair of Maxxis Rekon+, which are 2.8″ wide.

The maximum you can go in width with this tire diameter is 3.0″, which is monstrously wide. Therefore, you need to consider whether you want more capability and brute force with the 29″ wheels, or better cornering and more swiftness with 27.5″ wheels.

Niner Air 9 SLX

This build is slightly different and has a Fox Float 34 Rhythm fork with 120 mm of travel. The groupset is Shimano SLX, which is considered to be a fantastic set of components for recreational and enthusiast trail riders.

The crankset is a Race Face 32T, whereas the SLX cassette has an 11-46T range, which offers less climbing prowess. This model also has hydraulic disc brakes, but this time they are Shimano M6000. The tires are 29×2.35, but you can fit it with 27.5″ wheels as well.

This model costs around $1,700, which makes it perfect for those who want all of the benefits of the Niner Air 9 frame, but are willing to save some money on slightly weaker components.

1-Star SRAM NX

Niner AIR 9 1-Star SRAM NX

If you’re not willing to spend additional money on those more expensive builds, you can get this one for just $1,500. For this money, you’ll still get a very decent setup that can power your demanding rides. This build sports a Rockshox Judy Gold fork with 120 mm of travel and an 11-speed SRAM NX drivetrain.

The cassette has an 11-42T range, so climbing extreme gradients might be challenging. However, the brakes are SRAM Level, the same as on the more expensive build, so you can still go fast when getting down.

Ideal for riders who want the quality and pedaling efficiency of Air 9 and do not plan to climb as much.

2-Star SRAM GX

This model costs $1,500, the same as the previous one, but it carries a slightly different lineup of components. Namely, on it, you’ll find a FOX 34 Float fork with 120mm of travel and a 1×12 SRAM GX drivetrain.

It has a 32T crankset and a 10-50T cassette, so it’s perfect for challenging climbs. The brakes are the tried and true SRAM Guide R hydraulic discs, which is a good choice for this money.

If you want to do a lot of climbing but want to pay a reasonable sum, then this 2-Star SRAM GX build is for you.

2-Star Swag-Pack Edition

This build is pretty much the same as the 2-Star NX Eagle model, but it comes with some accessories in the bag. The Swag-Pack features include a:

  • camelback podium water bottle
  • Niner beanie
  • stainless Niner coffee mug
  • frame cargo strap
  • and an assortment of cargo stickers. This luxurious package will set you back $1,950.

Air 9 NX Eagle

The Niner 9 Air

This NX Build costs $1,700, so it’s cheaper than the most expensive model. For this kind of money, you will see a pair of Shimano M6000 hydraulic brakes and a dropper post, whereas everything else is the same.

This is the only model with a dropper post, so if that feature matters to you, then it’s the right choice for you.

Air 9 RDO Highlights

Niner 9 RDO

The Niner Air 9 RDO is a different creature than its cousin AIR 9, but it’s similar in many regards. You could say that it is Air 9 on steroids and you would not be wrong.

This bike has a super lightweight, stiff, and durable hardtail carbon frame. It’s Niner’s flagship carbon frame that’s built to be efficient and compliant and help you feel the trail and fight it at the same time.

The Niner Air 9 RDO has a slightly different geometry. Namely, the head tube angle is 69 degrees with 120mm of travel and 70 degrees with 100mm of travel. Moreover, the seat tube angle is 72 degrees. Therefore, you will be in a more upright position and have better control of the bike and a better overlook of the trail in front of you.

This Niner model is also compatible with Di2 systems and can be run as a single-speed bike. This is possible thanks to the BioCentric bottom bracket system, which lets you have it your way.

It weighs just around 21.7 lbs, depending on the build. Therefore, this is an amazing choice for those who wish to compete and win in XC and Trail competitions.

5-Star X01 Eagle 29

Image result for AIR 9 RDO 5-Star X01 Eagle

This is the most expensive build and costs $6,800. But, the buy is worth every penny. It has a 12-speed SRAM X01 Eagle groupset with a FOX 32 SC fork that offers 100 mm of travel. The tires are Maxxis Rekon, 2.4/2.25″ wide front, and back, so grip is not an issue.

Moreover, the SRAM Guide RSC brakes will stop on a dime whenever you need them to. The SRAM Eagle XG cassette has a 10-50T range, so climbing is not a problem with this bike if you have the legs to power it.

It’s absolutely the best choice you have if you’re serious about XC and Trail riding and you’re not willing to make any compromises.

See The Selection On JensonUSA



4-Star X01 Eagle 29

Niner Air 9 RDO 4-star in blue

This build costs $5,400, but the only difference it has with the 5-star build is the wheels. This model has a set of Stan’s Notubes Arch S1 wheels and Neo hubs, whereas the above model has more capable Stan’s Notubes Arch CB7 and Neo Ultimate hubs.

3-Star GX Eagle 29

AIR 9 RDO 3-Star GX Eagle

This 3-Star build makes some compromises compared to the two previous models since it costs $4,300. You’ll still get the same FOX 100mm fork and Stan’s Arch S1 wheels. However, the groupset is a 12-speed SRAM GX Eagle, with a 10-50 Eagle XG cassette. The brakes and other components are entirely the same.


2-Star NX Eagle 29

RDO 2-star

The 2-Star NX Eagle costs $3,000 and differs from the others in many regards. First of all, it has a FOX 32 Float Rhythm fork with 100mm of travel and Niner alloy wheels.

The tires are the same as on the previous models, the brakes are SRAM Level. The SRAM NX Eagle groupset offers 12 speeds with a high-range 10-50 SRAM PG cassette which is perfect for climbing. It’s a fantastic budget choice, but there’s an even better.

AIR 9 RDO GX Eagle


Cheapest option

This is the cheapest option you have if you want to get a Niner Air 9 RDO. It costs around $2,500, but still delivers a lot even at that price. It features an SRAM GX Eagle groupset which performs beautifully while still keeping the price down. The FOX 34 Float fork offers 120mm of travel, for the plushest obstacle tackling.

This build also has 12 speeds and a wide-range cassette, so you will not be limited by any terrain. This statement is reinforced by the Shimano M6000 brakes, which have a ton of stopping power.

Check availability – JensonUSA

3.3 Total Score

User Rating: 3.26 (57 votes)