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.

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. 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.

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.

“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.

Reynolds 853 stee

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.

"New trends in geometry and componentry are inspiring some really fun bikes, even for those who don't consider themselves the hardtail type."

"Niner has just released the latest drool-worthy steel hardtail with a bikepacking predisposition."

"It's still steel and 29in, but the new SIR 9 from Niner has a whole load more versatility built into it."

"The latest SIR 9 is an attractive option for riders who want a classic material in an up-to-date, versatile package."

SIR 9

$0.00

In stock

SKU

SIR-9

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SIR 9 5-STAR SRAM X01 EAGLE Specifications

Our premium, 5-Star SRAM X01 Eagle build kit and the reliable SIR 9 frame will give you smiles for miles. With 120mm of premium FOX front suspension and DT Swiss XMC 1501 SPLINE wheels, riding so far and so hard was never so easy.

DT Swiss XMC 1501 SPLINE 30 carbon wheels
FOX 34 SC Float Factory EVOL FIT 4 fork w/Kashima coat, 120mm travel
KS LEV SI dropper post

Available frame sizes	SM, MD, LG, XL	Available colors	CEMENT GRAY/BLACK
Frame	HAND WELDED AIR HARDENED REYNOLDS 853 STEEL; EXTERNAL CABLE ROUTING; INTEGRATED BOTTLE, BAG, RACK AND FENDER MOUNTS; 12X148 THRU AXLE	Fork	FOX 34 SC FLOAT FACTORY EVOL FIT4, 3 POSITION W/ ADJ, KASHIMA COAT, 120MM, 110X15MM, 44MM OFFSET
Shock	N/A	Tubes / Sealant	STANS NO TUBES SEALANT (2 X 2oz BOTTLES)
Front wheel	DT SWISS XMC 1501 SPLINE 30, CENTERLOCK, 110X15MM	Rear wheel	DT SWISS XMC 1501 SPLINE 30, CENTERLOCK, 148X12MM, RATCHET EXP 36
Front Tire	SCHWALBE NOBBY NIC EVO SUPER TRAIL TLE ADDIX SPEEDGRIP 2.6	Rear tire	SCHWALBE NOBBY NIC EVO SUPER TRAIL TLE ADDIX SPEEDGRIP 2.35
Brakes	SRAM G2 RSC	Brake levers	SRAM G2 RSC
Brake rotors	180/160 CENTERLINE X ROTORS	Chain	SRAM X01 EAGLE 12SP
Front shifter	N/A	Rear shifter	SRAM X01 EAGLE 12SP
Front derailleur	N/A	Rear derailleur	SRAM X01 EAGLE 12SP
Cassette	SRAM EAGLE XG 1295, 10-52T	Crankset	SRAM X1 EAGLE CARBON DUB 32T CNC RING
Bottom bracket	SRAM DUB PF30	Saddle	NINER CUSTOM TR WITH CRN-TI RAILS, PRINTED NINER GRAPHIC
Seatpost	KS LEV SI (XS/S-100MM, M/L/XL-150MM)	Handlebar	RACE FACE NEXT R 800MM WIDE, 35MM RISE, 35MM CLAMP
Stem	RACE FACE TURBINE R 40MM, 35MM CLAMP	Headset	NINER INTERNAL ZS SHIS DESCRIPTION ZS44/28.6\|ZS56/40
Grips	NINER GRRRIPS L/O SOFT COMPOUND	Approximate weight

GEOMETRY CHART

TECHNICAL SPECIFICATIONS

frame mounts and fittings	2 Inner Triangle Bottle Mounts, 1 Mount Under Down Tube, 1 on top tube, rack and fender mounts.	Rear suspension travel	n/a
Maximum front suspension	120mm	Fork offset	44mm
Shock size	n/a	Shock mounting hardware	n/a
Suggested shock sag	n/a	Seatpost size	30.9mm
Seat collar size	34.9mm	Cable routing	external
Front derailleur type	34.9 side swing, front pull	Headset size	1.125" X 1.5" Tapered Zero Stack Head Tube, 44mm Upper, 56mm Lower, Cane Creek Description: ZS44/28.6 ZS56/40
Pivot bearing specs	n/a	Chainring compatibility	Compatible With Standard 1X, 2X And 3X Systems
Maximum chainring size	1x max chain ring size: 36T - Boost Chainring Recommended	Q-Factor	168mm
ISCG compatibility	no	Bottom bracket type	73mm PF30 BB Shell (Adapters Required For BSA Type BBs); compatible with Biocentric 30 BB
Brake mount type	Post mount	Maximum rear rotor size	180mm
Rear wheel spacing	Boost 12x148mm	Rear wheel through-axle spec	M12x1.75Px182L
Front wheel axle spacing	Boost 15x110mm	Front wheel through-axle spec
Max tire size	29x2.4 or 27.5x3.0 Tire (Tire Sizes Vary By Brand, Some Tires May Not Fit)

SIR 9

Steel is real.

Made from metal

SIR 9: rugged, reliable, comfortable Reynolds 853 steel

Yes, SIR

Get real with Reynolds 853 steel

“Trail country” geometry

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

Reynolds 853 stee

Multiple mounting options

Biocentric 30

Trail ready geometry

Integrated dropper post routing

Lifetime warranty

Tire clearance

SIR 9

SIR 9 5-STAR SRAM X01 EAGLE Specifications

SIR 9 5-STAR SRAM X01 EAGLE Specifications

SIR 9 4-STAR SHIMANO XT Specifications

SIR 9 3-STAR SRAM GX EAGLE Specifications

SIR 9 3-STAR SHIMANO SLX SINGLESPEED Specifications

SIR 9 2-STAR SRAM SX EAGLE Specifications

SIR 9 FRAME ONLY Specifications