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    Niner SIR 9 Bike

    SIR 9

    Steel is real.

    Made from metal

    SIR 9: rugged, reliable, comfortable Reynolds 853 steel 

    There’s a new bike in town. It’s built to last and not let you down. When you’re spinning up the steeps, bombing down the backcountry and grinding out the final miles as the sun sinks into the horizon, you need a bike you can trust. A comfortable, capable, hand-built bike made from proven, air-hardened, heat-treated steel. That’s right, steel. Because Steel Is Real and it’s fully optimized in the SIR 9.

    Niner SIR 9 Bike Frame

    Yes, SIR

    So what’s the story with our steel hardtail? For starters, it’s STEEL. This classic metal alloy from materials icon Reynolds gives us the comfortable, durable, capable, versatile, “ride it hard and put it away wet” frame that we have always wanted.

    To make it even more tasty, the SIR 9 is strapped with a 120mm travel FOX suspension fork, perforated with no fewer than 18 threaded, reinforced mounting points, clears 29x2.4” (or 27.5x3.0”) tires, and offers easy options for geared or singlespeed drivetrains. We’ve even got custom frame bags made by Defiant Packs in Carbondale, Colorado. No excuses - pack an extra jacket and a PBR, go farther, and stay out longer.

    The SIR 9 is perfect for just about any type of riding, no matter how long or short. It’s a butt-kicking, grin-inducing lunch ride launch pad when you only have 30 minutes to burn in the back lot. It’s also made for multi-day missions in the backcountry. And it’s made to make you happy the minute you throw a leg over it.

    Niner Reynolds 853 & SIR 9 Bike

    Get real with Reynolds 853 steel

    This modern metal alloy is well known for its unique properties. It actually strengthens in the tube junctions when it air-cools after welding. So, we can do more with it, yet we actually can use less material. For instance, we can design intricate chainstay and seat-stay yokes to accommodate either 29” or 27.5-Plus wheels and tires, with plenty of mud clearance to spare. We also don’t need to add heavy gussets and tube reinforcements - it’s plenty strong as-is.

    Niner SIR 9 Bike Geometry

    “Trail country” geometry

    Blurring the lines between modern trail bike geometry and traditional cross-country geometry, the SIR 9 occupies a niche we lovingly call “trail country.” If you’re doing a combination of long pedaling rides, stiff climbs, extended descents, and spicy technical sections, you’ll love what we’ve done here. “Trail country” geometry translates to modern trail manners when you need them most, with no sacrifice of efficiency or agility. 

    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.

    Pack it up, pack it in, let me begin...

    The versatility of steel gives us the option to add accessory mounting points, and boy did we ever. There are rack and fender mounts, bottle cage mounts, frame bag mounts, and even a top-tube bento box mount. The rear rack mounts are strong enough to hold 55lbs.

    Niner SIR 9 Bike Frame

    Reynolds 853 steel

    The magic air-hardened metal from Reynolds actually strengthens after welding. Read More

    Multiple mounting options

    No fewer than 18 mounting points give you the freedom to run racks, fenders, bottles, frame bags, a bento box, and more. Read More

    Biocentric 30

    Do you yearn for simplicity? Our patented BioCentric bottom bracket system gives you the freedom to easily go single-speed or geared. Read More

    Trail ready geometry

    With a longer top tube and slacker head tube angle, the SIR 9 is stable, trail-specced and ready to get shreddy in all circumstances.

    Integrated dropper post routing

    Clean and concealed, SIR 9 is ready with ports on the seat tube for internal dropper post cable routing.

    Lifetime warranty

    Ride, race, rally. We have you covered with warranty service, small parts, and a support team that actually answers the phone. Read More

    Tire clearance

    Need room to roam? We got it. The SIR 9 has clearance to run your choice of 29er or 27.5+ wheels and tires.

    Specifications

    Premium parts and a reliable frame will give you smiles for miles. With 120mm of premium FOX suspension and Stan’s ARCH CB7 wheels, riding so far and so hard was never so easy.

    • Stan’s NoTubes ARCH CB7 rims with Neo Ultimate hubs
    • FOX 34 SC Float Factory FIT 4 EVOL fork w/Kashima coat, 120mm travel
    • KS LEV SI dropper post
    Available frame sizesSM, MD, LG, XLAvailable colorsSlate blue/orange
    FrameHAND WELDED AIR HARDENED REYNOLDS 853 STEEL; EXTERNAL CABLE ROUTING; INTEGRATED BOTTLE, BAG, RACK AND FENDER MOUNTS; 12X148 THRU AXLEForkFOX 34 SC FLOAT FACTORY EVOL FIT4, 3 POSITION W/ ADJ, KASHIMA COAT, 120MM, 110X15MM, 44MM OFFSET
    ShockN/ATubes / SealantSTANS NO TUBES SEALANT (2 X 2oz BOTTLES)
    Front wheelSTANS NOTUBES ARCH CB7 29er, NEO ULTIMATE HUB 110X15MM FRONTRear wheelSTANS NOTUBES ARCH CB7, NEO ULTIMATE HUB 148X12MM REAR
    Front TireMAXXIS MINION DHF 3C/EXO/TR 2.5 WT FRONTRear tireMAXXIS REKON 3C/EXO/TR 2.4 WT REAR
    BrakesSRAM G2 RSCBrake leversSRAM G2 RSC
    Brake rotors180/160 CENTERLINE ROTORSChainSRAM X01 EAGLE 12SP
    Front shifterN/ARear shifterSRAM X01 EAGLE 12SP
    Front derailleurN/ARear derailleurSRAM X01 EAGLE 12SP
    CassetteSRAM EAGLE XG 1295, 10-50TCranksetSRAM X1 EAGLE CARBON DUB 32T CNC RING
    Bottom bracketSRAM DUB PF30SaddleNINER CUSTOM TR WITH CRN-TI RAILS, PRINTED NINER GRAPHIC
    SeatpostKS LEV SI (XS/S-100MM, M/L/XL-150MM)HandlebarRACE FACE NEXT R 800MM WIDE, 20MM RISE, 35MM CLAMP
    StemRACE FACE TURBINE R 40MM, 35MM CLAMPHeadsetNINER INTERNAL ZS SHIS DESCRIPTION ZS44/28.6|ZS56/40
    GripsNINER GRRRIPS L/O FLANGEDApproximate weight

    This 4-Star SIR 9 is dressed for success with a light, stiff FOX 34 120mm travel suspension fork, Shimano XT drivetrain, and DT Swiss M1900 wheels. No excuses - get out and ride!

    • DT Swiss M1900 wheels
    • FOX 34 SC Float Factory FIT 4 EVOL fork w/Kashima coat, 120mm travel
    • KS LEV SI dropper post
    Available frame sizesSM, MD, LG, XLAvailable colorsSLATE BLUE/ORANGE
    FrameHAND WELDED REYNOLDS 853 STEEL; EXTERNAL CABLE ROUTING; INTEGRATED BOTTLE, BAG, RACK AND FENDER MOUNTS; 12X148 THRU AXLEForkFOX 34 SC FLOAT FACTORY EVOL FIT4, 3 POSITION W/ ADJ, KASHIMA COAT, 120MM, 110X15MM, 44MM OFFSET
    ShockN/ATubes / SealantSTANS NO TUBES SEALANT (2 X 2oz BOTTLES)
    Front wheelDT SWISS M1900 SPLINE 30, DT370 CENTERLOCK HUB 110X15MM FRONTRear wheelDT SWISS M1900 SPLINE 30, DT370 CENTERLOCK HUB 148X12MM REAR
    Front TireMAXXIS MINION DHF 3C/EXO/TR 2.5 WT FRONTRear tireMAXXIS REKON 3C/EXO/TR 2.4 WT REAR
    BrakesSHIMANO XT M8100, METAL PAD W/ FINBrake leversSHIMANO XT M8100
    Brake rotors180/160 CENTERLINE ROTORSChainSHIMANO XT M8100 W/ QUICKLINK
    Front shifterN/ARear shifterSHIMANO XT M8100 12SP I-SPEC EV
    Front derailleurN/ARear derailleurSHIMANO XT M8100 SGS 12SP
    CassetteSHIMANO XT M8100 12SP, 10-51TCranksetRACEFACE NEXT R CARBON 12SP, 32T
    Bottom bracketRACEFACE PF30SaddleNINER CUSTOM TR WITH CRN-TI RAILS, PRINTED NINER GRAPHIC
    SeatpostKS LEV SI (XS/S-100MM, M/L/XL-150MM)HandlebarRACE FACE NEXT R 800MM WIDE, 20MM RISE, 35MM CLAMP
    StemRACE FACE TURBINE R 40MM, 35MM CLAMPHeadsetNINER INTERNAL ZS SHIS DESCRIPTION ZS44/28.6|ZS56/40
    GripsNINER GRRRIPS L/O FLANGEDApproximate weight

    Expect the best from Shimano's new XT drivetrain. Mated to our SIR 9 frame and FOX 34 Performance suspension, every feature of this adventure-seeking singletrack slayer is fully optimized.

    • DT Swiss M1900 wheels
    • FOX 34 SC Float Performance Elite EVOL FIT4, 3 position, 120mm, 110X15mm, 44mm offset
    • KS LEV SI dropper post
    Available frame sizesSM, MD, LG, XLAvailable colorsSLATE BLUE/ORANGE
    FrameHAND WELDED REYNOLDS 853 STEEL; EXTERNAL CABLE ROUTING; INTEGRATED BOTTLE, BAG, RACK AND FENDER MOUNTS; 12X148 THRU AXLEForkFOX 34 SC FLOAT PERFORMANCE ELITE EVOL FIT4, 3 POSITION W/ ADJ, 120MM, 110X15MM, 44MM OFFSET
    ShockN/ATubes / SealantSTANS NO TUBES SEALANT (2 X 2oz BOTTLES)
    Front wheelDT SWISS M1900 SPLINE 30, DT370 CENTERLOCK HUB 110X15MM FRONTRear wheelDT SWISS M1900 SPLINE 30, DT370 CENTERLOCK HUB 148X12MM REAR
    Front TireMAXXIS MINION DHF 3C/EXO/TR 2.5 WT FRONTRear tireMAXXIS REKON 3C/EXO/TR 2.4 WT REAR
    BrakesSHIMANO XT M8100, METAL PAD W/ FINBrake leversSHIMANO XT M8100
    Brake rotors180/160MM SM-RT70 ROTORSChainSHIMANO SLX M7100 W/ QUICKLINK
    Front shifterN/ARear shifterSHIMANO XT M8100 12SP I-SPEC EV
    Front derailleurN/ARear derailleurSHIMANO XT M8100 SGS 12SP
    CassetteSHIMANO XT M8100 12SP, 10-51TCranksetRACEFACE TURBINE 12SP, 32T
    Bottom bracketRACEFACE PF30SaddleNINER CUSTOM TR WITH CRN-TI RAILS, PRINTED NINER GRAPHIC
    SeatpostKS LEV SI (XS/S-100MM, M/L/XL-150MM)HandlebarRACE FACE AEFFECT R 780MM WIDE, 20MM RISE, 35MM CLAMP
    StemRACE FACE TURBINE R 40MM, 35MM CLAMPHeadsetNINER INTERNAL ZS SHIS DESCRIPTION ZS44/28.6|ZS56/40
    GripsNINER GRRRIPS L/O FLANGEDApproximate weight

    SRAM does it again with a wallet friendly, high-performing parts kit. Mated to our SIR 9 frame and Marzocchi suspension, every feature of this adventure-seeking singletrack slayer is fully optimized.

    • Niner wheels
    • Marzocchi Bomber Z2 fork, 120mm travel
    • Niner Alloy seatpost
    Available frame sizesSM, MD, LG, XLAvailable colorsSLATE BLUE/ORANGE
    FrameHAND WELDED REYNOLDS 853 STEEL; EXTERNAL CABLE ROUTING; INTEGRATED BOTTLE, BAG, RACK AND FENDER MOUNTS; 12X148 THRU AXLEForkMARZOCCHI BOMBER Z2 RAIL, SWEEP ADJ, 120MM, 110X15MM, 44MM OFFSET
    ShockN/ATubes / SealantSTANS NO TUBES SEALANT (2 X 2oz BOTTLES)
    Front wheelNINER ALLOY, 110X15MM FRONT, NINER GRAPHICRear wheelNINER ALLOY, 148X12MM REAR, NINER GRAPHIC
    Front TireMAXXIS MINION DHF 3C/EXO/TR 2.5 WT FRONTRear tireMAXXIS REKON 3C/EXO/TR 2.4 WT REAR
    BrakesSRAM LEVELBrake leversSRAM LEVEL
    Brake rotorsSRAM LEVELChainSRAM SX EAGLE 12SP
    Front shifterN/ARear shifterSRAM SX EAGLE 12SP
    Front derailleurN/ARear derailleurSRAM SX EAGLE 12SP
    CassetteSRAM PG 1210 11-50TCranksetSRAM X1 1K EAGLE DUB, 32T
    Bottom bracketSRAM DUB PF30SaddleNINER CUSTOM TR WITH CRN-TI RAILS, PRINTED NINER GRAPHIC
    SeatpostKS LEV SI (XS/S-100MM, M/L/XL-150MM)HandlebarRACE FACE AEFFECT R 780MM WIDE, 20MM RISE, 35MM CLAMP
    StemRACE FACE TURBINE R 40MM, 35MM CLAMPHeadsetNINER INTERNAL ZS SHIS DESCRIPTION ZS44/28.6|ZS56/40
    GripsNINER GRRRIPS L/O FLANGEDApproximate weight
    Available frame sizesSM, MD, LG, XLAvailable colorsSLATE BLUE/ORANGE
    FrameHAND WELDED REYNOLDS 853 STEEL; EXTERNAL CABLE ROUTING; INTEGRATED BOTTLE, BAG, RACK AND FENDER MOUNTS; 12X148 THRU AXLE

    Niner Bikes reserves the right to change bike assembly specification at any time without notice. While we make every effort to publish accurate build specs, substitutions and/or running changes may be made without warning.

    Niner SIR 9 Bike Specs
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