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2021 Niner SIR 9 4-Star Bike

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Product Niner SIR 9 4-Star Bike
Model Year 2021
Riding Type Cross Country, Trail
Rider Unisex
Sizes and Geometry
SM, MD, LG, XL View Geometry
Top Tube Length 595mm 603mm 627mm 652mm
Head Tube Angle 68° 68° 68° 68°
Head Tube Length 100mm 110mm 125mm 145mm
Seat Tube Angle 74° 74° 74° 74°
Seat Tube Length 396mm 421mm 485mm 533mm
Bottom Bracket Height 52mm drop 52mm drop 52mm drop 52mm drop
Chainstay Length 427mm 427mm 427mm 427mm
Wheelbase 1118mm 1136mm 1162mm 1189mm
Standover 721mm 739mm 791mm 830mm
Reach 410mm 425mm 445mm 465mm
Stack 611mm 620mm 634mm 652mm
Wheel Size 29"
Frame Material Steel
Frame Material Details Hand-welded air-hardened heat-treated Reynolds 853 steel
Rear Travel Hardtail
Rear Shock None
Fork FOX FLOAT 34 Step-Cast (SC) Factory, EVOL, FIT4 damper, 3-position with adjust, Kashima coating, 44mm offset
Fork Travel 120mm
Head Tube Diameter Tapered, 1.125" top, 1.5" bottom
Headset Niner Internal, ZS44/28.6 upper, ZS56/40 lower
Handlebar Race Face Next R, 800mm width, 20mm rise, 35mm clamp diameter
Stem Race Face Turbine R, 40mm length, 35mm bar clamp
Grips Niner Grrrips, lock-on, soft compound
Brakes Shimano Deore XT M8100, 2-piston, metal pads with cooling fins, Shimano MT800 CENTER LOCK rotors (180mm front, 160mm rear)
Brake Levers Shimano Deore XT M8100
Drivetrain 1x
Shifters Shimano Deore XT M8100, 12-speed, I-SPEC EV bracket
Front Derailleur None
Rear Derailleur Shimano Deore XT M8100, 12-speed, SGS cage
ISCG Tabs None
Chainguide None
Cranks Race Face Next R Carbon
Chainrings Race Face Next R, 32 tooth
Bottom Bracket Race Face, PF30 press-fit
Pedals None
Chain Shimano Deore XT M8100, with QUICK-LINK
Cassette Shimano Deore XT M8100, 12-speed, 10-51 tooth
Rims DT Swiss XM 1700 Spline 30 wheelset
Hubs DT Swiss XM 1700 Spline 30 wheelset, 110x15mm Boost front, 148x12mm Boost rear with MICRO SPLINE driver
Spokes DT Swiss XM 1700 Spline 30 wheelset
Tires Schwalbe Nobby Nic, Evo, Super Trail, TLE, Addix Speedgrip, 29" x 2.6" (front), 2.35" (rear)
Saddle Niner Custom TR, CrN-Ti rails
Seatpost KS LEV SI dropper
Drop: 100mm (SM), 150mm (MD/LG/XL)
Seatpost Diameter 30.9mm
Seatpost Clamp Single bolt, 34.9mm
Rear Dropout / Hub Dimensions 148x12mm Boost
Max. Tire Size 29" x 2.4" or 27.5" x 3.0"
Bottle Cage Mounts Two inside front triangle, one under down tube, plus accessory mounts on top tube
Colors Cement Grey/Black
Warranty Lifetime frame, 5 years Niner components, 1 year paint/decals
Weight 27 lb 11.2 oz (12,565 g)
Miscellaneous - External cable routing, with internal dropper post routing
- Includes Stan's NoTubes sealant
- Singlespeed compatible with BioCentric 30 bottom bracket system
- Compatible with 27.5+ wheels/tires
- Rack and fender mounts
- Weight given for size MD
Price $4,600
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