Niner 2021 AIR 9 3-Star SS Hardtail Mountain Bike (Silver/Baja Blue) (LTD)

Price: $2,090.00
Discontinued Online
This item is discontinued and no longer available for purchase. You may want to search our site for a similar item.

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.

If you're looking for a dose of simplicity, this 3-Star Shimano singlespeed build is your ticket. Single Speed bikes are lighter, simpler, quieter, and often more reliable than their geared counterparts. With purity comes peace. 


  • 6061 Aluminum Frame: Hydroformed aluminum blends stiffness and comfort in a durable package. 
  • Race Face bar and stem: for outstanding performance and durability
  • Shimano SLX cranks and Niner Cogalicious single-speed drivetrain: simplicity at it's finest
  • 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: Shimano XT M8100, Metal Pad w/fin 
Brake Levers: Shimano XT M8100     
Brake Rotors: 180mm / 160mm Shimano XT RT-86
Shifters: N/A
Derailleurs: N/A
Cable routing: External   
Headset: Niner Integrated SHIS description: IS42/28.6 IS52/40)   
Chain: SRAM 1speed   
Crankset: Shimano SLX M7000 (32T) 
Cassette: Niner Cogalicious, 20T  
Bottom Bracket: Niner Biocentric 30
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 October 19, 2020

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"