Introduction by Francis Cebedo

What is the purpose of this steel hardtail that is designed for a 120mm or 140mm front fork? Well the purpose is to 'Ride Over ****' and that's why it's called the ROS 9. But is there really a market for a 29er hardtail bike that is not optimized for Cross Country or Racing? Can a 29er hardtail be fun?

We think so. This is part of a new segment of bikes we like to call 'rally hardtails'. The more common term is All Mountain hardtails and other companies like Banshee and Canfield have been forging the way for public to discover this new kind of hardtail that can tackle rough terrain. In general, they have lots of travel in front and none on the rear. Slack head angles and short chain stays are part of the equation. And in recent months, the dropper seatpost has become part of the formula. The 29er wheel is a key component as well since that 0 mm of rear travel needs all the help it can get.

All seems very alien right? Well we tried the Trek Stache 8 ourselves and warmed up to the idea. Here is a bike that doesn't cost very much yet is comfortable in the tightest singletrack, drops, jumps and flow trails. With a dropper post, some big volume, tubeless tires running low pressure, this bike can rally.



The numbers on this Niner ROS 9 check out just fine. The chainstay length is 16.8 inches and that is indeed short. Most hardtails are at around 17.5 inches and even Niner's own SIR 9 is at 17.3 inches. This is good as short stays translates to agility, traction and fun. The BB height stays the same as the already low Niners at a 2.2 inch drop. The other key metric is the head angle. Is it slack? Oh yes, it's slack at 68 degrees with a 120 mm fork and 67 degrees with a 140 mm fork.

And then the other key feature is internal cable routing for a dropper post. Such is a new concept in hardtails but there is no question that they will be the norm in 3-5 years because they extend the range and the playfulness of a bike so much. Another feature to note is a 142x12 Maxle rear axle to keep the rear end as laterally stiff as possible.

And of course let's not forget that this is steel with 29er wheels. This will give the rear of the bike that extra cush as the front of the bike is likely to get in to all sorts of ruckus.

So we're excited. $900 gets you the frame and $2500 gets you a bike in their base 1-Star X7 Kit.

Continue reading for details on the frame and full photo gallery.



From the Manufacturer

The hardtail for riders that don't like hardtails. No twitchy high-posting around features you would hit on your "real" bike. No need to back off because your XC racing head angle prevents solid roosting. The ROS 9 won't judge your lines - it lets you write checks your skills might not be able to cash, and what is more exhilarating than that? Short chainstays, slack head angle, and oversized headtube nourish these Roots of Steel - all with the ability to tweak the geometry via the BioCentric II. Run this rig singlespeed, 1x or fully geared with a front derailleur if you roll that way. Remove the cable guides and front derailleur mount if you don't. Stealth routing for the dropper post keeps the ROS 9 fresh and clean. Sorry, the ROS 9 is not compatible with heart rate monitors or training plans but it will certainly earn you some PRs when you do your part keeping the rubber side down. Ride Over S*!t - The new ROS 9 injects hardtails with a huge-ass dose of fun.

Highlights

  • Rowdy steel radnesss from the 29er-only mountain bike company
  • Zero mm of suspension is efficient in every chainring
  • 44mm OS headtube is compatible with 120-140mm forks
  • Geometry is slack and low with extra-short chainstays
  • Biocentric II enables perfect singlespeed setup and allows geometry fine-tuning
  • Forged frame details and internal or external dropper post routing
  • 142mm x 12mm rear spacing

What Makes the ROS 9 Tick?

The 4130 Cro-Mo tube set of the ROS 9 is the trusted standard for durability and ride quality. Following the lines and design language of the SIR 9, these tubes have been beefed up to handle the abuse the ROS 9 is designed to shrug off. The super-short chainstays provide a lofty front end feel while the slack headtube angle keeps the front end composed at Mach Loony speeds. A neutral BB height can be made low or high to slay YOUR trails by positioning the BioCentric II where it will do the most good.

Construction details abound - We borrowed the unique dropout design we developed for the SIR 9 to allow 142x12mm Maxle use and house the stout alloy derailleur hanger. The dropout designs allow the chain stays and seat stays to be welded at any angle and provide far more surface area for a full weld around the tube's end. The front derailleur hanger is removable with an alloy cover. Internal dropper post routing is optional, another alloy cover closes the port if you choose not to use it. Externally routed dropper posts utilize mounts under the top tube. Tabs under the bottom bracket shell accept an proprietary MRP XCG bash guard for optional extra protection. Full-housing cable routing for front and rear derailleurs using Niner's bolt-on double housing clamps along top and down tubes complete the versatility. If you don't need the guides, take them off and enjoy the clean look of the frame in singlespeed mode.

Oversized Headtube

The oversized headtube of the ROS 9 allows the use of tapered fork steerer tubes that measurably reduce fork deflection, which means your Niner tracks straight and true. The full spectrum of riders from xc racers to all mountain shredders benefit from these features which is why we incorporate the technology in all our new frames. The ROS 9 Lets you take full advantage of increased steering precision as you get yourself into trouble.



Bio-Centric II Bottom Bracket System

The Niner BioCentric II makes adjustments easy across a wide range of gears and eliminates the need for adjustable dropouts, giving the cleanest possible solution for singlespeed use. No bolt on hubs, no chain tensioners cluttering your ride, no brake adjust¬ments with gear changes. Additionally, BB positioning allows fine-tuning of geometry. Want shorter chainstays? A lower BB? Steeper or slacker seat angle? It's all achievable with the BioCentric II.

Greater Range - The BioCentric II offsets the bottom bracket spindle 8.5mm from center, offering greater range of adjustment compared to a traditional EBB setup. More offset is a boon when changing gears without having to change chain length and it al¬lows riders to make more noticeable changes to frame geometry.

Reliable Function - Traditional EBB units are held in place with set screws that can become difficult to finely adjust over time, or ex¬pansion wedges that can deform the bottom bracket shell of the frame. Split bottom bracket shells that clamp an EBB can stretch or ovalize. The Bio-Centric II avoids these troubles by using two bolts to apply a clamping force on the outside edges of the BB shell, eliminating the possibility of ovalizing or indexing the shell.



ROS 9 Specifications & Compatibility

  • 73mm BB width (with BioCentric II installed)
  • BioCentric II is compatible with external bearing cranksets only
  • Direct mount front derailleur, high mount, top pull, removable front derailleur mount
  • Tabs under BB shell for custom MRP XCG Bash Guard - available separately at www.ninerbikes.com
  • 31.6mm seat post size, compatible with internal and external dropper post routing
  • 34.9mm seat collar size
  • 44mm headtube. Tapered headset with internal (ZS) top cup and 1.5" external bottom cup (included with frame). Cane Creek standard description: ZS44/28.6|EC44/40
  • All sizes have one bottle mount in the front triangle
  • Replaceable derailleur hanger or SS insert
  • 142 x 12mm Maxle rear spacing
  • Can fit up to a 2.35" tire (tire size varies by brand, some tires may not fit)
  • Compatible with most standard 1x, 2x and 3x chainring systems.
  • Max 1x chainring size 32T with BioCentric II in rear position - Max 38T with BioCentric II in forward position



New ROS 9 ★★★★ X01 Star Builds

  • Frame: Niner ROS 9, Rally Blue
  • Fork: RockShox Revelation RCT3 Solo Air 130mm, 15mm, Rally Blue
  • Wheelset: NoTubes 3.30/ZTR Flow EX, 15mm Front, 142 x 12mm Rear
  • Tires: Schwalbe Nobby Nic Snakeskin TL, 2.35
  • Brakes & Rotors: SRAM Elixir 9 Trail, 180 / 160mm G2 Rotors
  • Brake Levers: SRAM Elixir 9 Trail, Black
  • R/Shifter: SRAM X01 11sp with Matchmaker
  • F/Shifter: N/A
  • R/Derailleur: SRAM X01 11sp
  • F/Derailleur: N/A
  • Cassette: SRAM XG 1195 11sp 10-42T
  • Chain: SRAM PC 1170
  • Crank Set: SRAM X01 GXP 32T
  • Bottom Bracket: SRAM GXP
  • Saddle: WTB Volt Race with Cr-Mo Rails, Niner Graphic
  • Seatpost: Niner Carbon Seat post, 400mm, Red, Niner Graphic
  • Handlebar: Niner Flat Top Alloy, 780mm, Red, Niner Graphic
  • Stem: Niner Alloy Stem
  • Grips: Niner Grrrips

For more information visit www.ninerbikes.com