Niner's SIR 9 is back!

The classic steel hardtail is back and more versatile than before

Niner’s classic steel hardtail is back and more versatile than before.

Niner SIR 9 highlights

  • Compatible with 29in and 27.5+ wheels and tires
  • Slacker geometry than the previous version
  • Reynolds 853 steel front triangle
  • Boost axle spacing
  • 18 mounting options for bottles, bags and other accessories
  • Redesigned chainstay yoke claimed to improve stiffness
  • Complete bikes pricing from $3,000 to $6,000 (UK and Aussie pricing TBC)
  • Frame-only pricing at $1,200 (UK and Aussie pricing TBC)
  • Available now

The SIR 9 can roll on 27.5+ (shown) or 29er wheels and tires
The SIR 9 can roll on 27.5+ (shown) or 29er wheels and tires

This ferrous-framed 29er still relies on high-quality Reynolds 853 steel for the main frame but with more trail-oriented geometry than its predecessors. It appears that Niner blended elements ROS 9 into the latest SIR 9.

"The new frame is really a fusion of the SIR with the high quality 853 steel, the ROS geometry, and the ROS 9 Plus versatility," said Brad Cole, Niner's marketing manager.

Unlike its cross-country focused predecessor, the new SIR 9 is designed around a 120mm travel fork. The 68-degree head tube angle is approximately three degrees slacker.

Reach numbers grow longer across the four-bike size range, while chainstay length shrinks by 13mm to 427mm/16.8in.

The SIR 9 is slacker than the previous version
The SIR 9 is slacker than the previous version

Versatile frame design

Integrated mounts for frame bags make the ROS 9 look very clean in bikepacking mode
Integrated mounts for frame bags make the ROS 9 look very clean in bikepacking mode

The new SIR 9 checks off a lot of boxes for a modern steel hardtail. It's compatible with a 30.9mm dropper seatpost and can be built up for a multitude of uses.

The frame uses a 73mm PF30 bottom bracket shell. Riders can convert the frame for singlespeed use by installing Niner’s Biocentric 30 bottom bracket system.

The SIR 9 uses a PF 30 bottom bracket shell
The SIR 9 uses a PF 30 bottom bracket shell

Many full suspension designs are now 1x-specific, but this hardtail still offers the option to run a 2x drivetrain with a side-swing front derailleur. 

Despite the big-wheel brand name, Niner has also embraced 27.5+ wheels and tires. The SIR 9 has clearance for 29x2.4 or 27.5x3in tires.

In addition to wheelsize versatility, the frame offers a pair braze-ons on the top tube for an integrated bento box.There are additional mounts in the mainframe so bikepackers can run a strapless frame bag. Lastly, a trio of mounts on the bottom of the down tube allow for an additional water bottle or cargo-carrying possibilities.

SIR 9 Pricing and availability

The SIR 9 is available as a complete bike or as a frame
The SIR 9 is available as a complete bike or as a frame

Niner offers the SIR 9 in nine different built kits with your choice of 27.5+ or 29er wheels. The options start with the $3,000 SLX kit and top out with the $6,000 XO Eagle build. (UK and Australian pricing have yet to be announced.)

The SIR 9 is available now. The frame-only version of the SIR 9 retails for $1,200. 

Visit www.ninerbikes.com for more information.

Josh has been riding and racing mountain bikes since 1998. Being stubborn, endurance racing was a natural fit. Josh bankrolled his two-wheeled addiction by wrenching at various bike shops across the US for 10 years and even tried his hand at frame building. These days Josh spends most of his time riding the trails around his home in Fort Collins, Colorado.
  • Discipline: Mountain, cyclocross, road
  • Preferred Terrain: Anywhere with rock- and root-infested technical singletrack. He also enjoys unnecessarily long gravel races.
  • Current Bikes: Trek Remedy 29 9.9, Yeti ASRc, Specialized CruX, Spot singlespeed, Trek District 9
  • Dream Bike: Evil The Following, a custom Moots 27.5+ for bikepacking adventures
  • Beer of Choice: PBR
  • Location: Fort Collins, CO, USA
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