Niner 2021 AIR 9 2-Star Hardtail Mountain Bike (Silver/Baja Blue) (XS)

Out Of Stock Online
Price: $1,800.00


  • XS
  • S
  • M
  • L
  • XL
View Size Chart

Please Log in to receive a notification when this item arrives in stock.

Save In List
Read Reviews
Write a Review
This item is eligible for Super Saver Shipping Learn More
This item earns up to 1800 VIP Reward Points Learn More

The Air 9 aluminum hardtail blends the agility and efficiency of a pedal-friendly XC bike with the versatility, toughness and capability of a rowdy trail rig. Lightweight and snappy, poppy and peppy, the AIR 9 has plenty of stiffness to get you up to speed when you stomp on the pedals.  
[R]evolution geometry puts the rider in the sweet, balanced spot on the bike. The roomy cockpit has a comfortable reach for short stem lengths, giving you quick handling and plenty of maneuverability to blast through rock gardens and cut hard corners. The steep 74-degree seat angle gets you centered over the BB for climbing and pairs nicely with the short 430mm chainstay length for supreme pedaling efficiency.. And of course, the slack, 68-degree head tube angle and long wheelbase contribute stability and self-confidence when you’re dropping into the steepest lines.

Hit the trail big with the 2-Star SRAM SX build, without a big hit to your wallet. Thanks to SRAM's outstanding SX Eagle drivetrain, you can bring every ounce of AIR 9 performance to bear at an affordable price level.  


  • 6061 Aluminum Frame: Hydroformed aluminum blends stiffness and comfort in a durable package. 
  • Race Face bar and stem: for outstanding performance and durability
  • SRAM SX Eagle drivetrain: wide range 1x gearing to tackle all obsticles
  • Marzocchi Bomber Z2 Rail suspension fork: 120mm of perfectly tuned suspension 
  • Niner Alloy wheels (Boost Spacing)
  • Lifetime Warranty: Ride, race, rally with confidence. Niner has you covered with warranty service, small parts, and a support team that actually answers the phone. Read more here >
  • Biocentric 30: BioCentric bottom bracket system gives you the freedom to easily go single-speed or geared. 

Due to availability issues during manufacturing, build specifications are subject to change. Please contact us if you wish to verify build specs before purchase.

Frame: Hydroformed and welded 6061-T6 Aluminum  
Fork: Marzocchi Bomber Z2 Rail (120mm)  
Color: Silver/Baja Blue    
Available frame sizes: XS, S, M, L, XL 
Shock: N/A  
Front Wheel: Niner alloy clincher (15 x 110mm TA)        
Rear Wheel: Niner alloy clincher (12 x 148mm TA) 
Front Tire: Schwalbe Nobby Nic Evo Super Trail TLE Addix SpeedGrip (2.60) 
Rear Tire: Schwalbe Nobby Nic Evo Super Trail TLE Addix SpeedGrip (2.35) 
Tubes/Sealant: Stans No Tubes Sealant (2x 20oz Bottles) 
Seat post: Niner Alloy Seat Post (270mm)         
Brakes: SRAM level       
Brake Levers: SRAM level           
Brake Rotors: 180mm / 160mm SRAM G2CS       
Shifters: N/A  (front), SRAM SX Eagle 12sp (rear)
Derailleurs: N/A (front), SRAM SX Eagle 12sp (rear)      
Cable routing: External    
Headset: Niner Integrated SHIS description: IS42/28.6 IS52/40)    
Chain: SRAM SX Eagle 12speed    
Crankset: SRAM X1 1K Eagle Dub (32T)       
Cassette: SRAM PG1210 (11-50T)       
Bottom Bracket: SRAM DUB PF30 
Handlebar: Race Face Aeffect R (780mm) (20mm Rise) (35mm Clamp)     
Stem: Race Face Aeffect R (40mm Length) (35mm Clamp)        
Grips: Niner Grrrips L/O Nylon soft compound  
Saddle: Niner Custom TR w/ cr-mo rails

*Note: These bikes are fully built by our expert bike builders, then partially disassembled as needed for shipping. Bikes will arrive to you with some basic assembly still required.  

This product was added to our catalog on December 15, 2020

Verified Owner
Thursday, Feb 4 2021 (9 months ago)
Niner 2021 AIR 9 2-Star Hardtail Mountain Bike (Silver/Baja Blue) (XS)
A beautiful build with quality components at an excellent price point. Niner has stayed true to its roots with a functional cross-country hardtail that is ready for the singletrack, gravel roads, fire roads, and more.

Heads up if you are buying the XS frame, I purchased this for my son who is 5 feet tall, the seat tube is curved which does not allow you to insert the seat post more than 5.5 inches so be ready to break out the hack saw or order a shorter seat post until the smaller rider can use the Niner alloy seat post that comes with the full build.

I highly recommend Niner as a brand and the Air 9 as an amazing full build hardtail!

Sizing Recommendations for Riders Who Fall Between Sizes:

  • Sizing down will provide a more maneuverable ride while sizing up will provide more stability
Rider Height (Feet)Rider Height (Meters)
XS5' - 5'5"1.53 - 1.65m
S5'3" - 5'9"1.6 - 1.75m
M5'8" - 6'1.73 - 1.83m
L5'11" - 6'3"1.8 - 1.91m
XL6'3" - 6'7"1.91 - 2.01m

Note: All sizing recommendations are provided by the manufacturer and may differ for each rider.


Note: Geometry chart is for 120mm of fork travel
(A) Top Tube Length570mm585mm603mm627mm652mm
(B) Seat Tube Length356mm394mm419mm483mm533mm
(C) Chainstay Length Actual430mm430mm430mm430mm430mm
(D) Horizontal Chainstay427mm427mm427mm427mm427mm
(E) Front Center678mm693mm711mm737mm764mm
(F) Wheelbase1102mm1117mm1136mm1162mm1189mm
(G) Bottom Bracket Drop52mm52mm52mm52mm52mm
(H) Headtube Length100mm100mm110mm125mm145mm
(I) Headtube Angle68.0°68.0°68.0°68.0°68.0°
(J) Seat Tube Angle74.0°74.0°74.0°74.0°74.0°
(K) Stand Over Height698mm729mm748mm800mm841mm
(L) Reach395mm410mm425mm445mm465mm
(M) Stack610610mm620mm634mm652mm
(A) Top Tube Length22.4"23.0"23.7"24.7"25.7"
(B) Seat Tube Length14.0"15.5"16.5"19.0"21.0"
(C) Chainstay Length Actual16.9"16.9"16.9"16.9"16.9"
(D) Horizontal Chainstay16.8"16.8"16.8"16.8"16.8"
(E) Front Center26.7"27.3"28.0"29.0"30.1"
(F) Wheelbase43.4"44.0"44.7"45.8"46.8"
(G) Bottom Bracket Drop2.05"2.05"2.05"2.05"2.05"
(H) Headtube Length3.9"3.9"4.3"4.9"5.7"
(I) Headtube Angle68.0°68.0°68.0°68.0°68.0°
(J) Seat Tube Angle74.0°74.0°74.0°74.0°74.0°
(K) Stand Over Height27.5"28.7"29.5"31.5"33.1"
(L) Reach115.5"16.1"16.7"17.5"18.3"
(M) Stack24.0"24.0"24.4"24.9"25.7"