Niner ROS 9 steel hardtail and JET 9 alloy full-suspension bikes

JET 9 sheds weight and adds travel while ROS goes big on front-end travel

Niner announced two new chassis to its expanding range of 29ers: the alloy JET 9 short-travel, cross-country, full-suspension machine and the intriguing ROS 9, an aggressive chromoly steel hardtail.

All-new JET 9 sheds weight, adds travel

Niner's short-travel JET 9 platform gets a complete overhaul for this year. Rear-wheel travel grows from 80mm to a more useful 100mm while the claimed frame weight drops to a more competitive 2.86kg (6.3lb) from the previous 2.97kg (6.55lb).

Weight was shaved nearly everywhere you look with updated forgings for the seat stay and chain stay yokes, all-new 142x12mm thru-axle rear dropouts, and a clever one-piece PF30 bottom bracket shell that directly integrates the forward lower linkage pivot and the lower shock mount. The main upper linkage pivot is now built right into the seat tube instead of the predecessor's extra welded-on mount and according to Niner, a switch from hydroformed aluminum tubes to air-formed ones (using superheated and pressurized air instead of oil to push the walls out against a steel die) allows for more precise wall thicknesses and greater cross-sectional variances from end-to-end, too.

Other features include Enduro Max full complement sealed cartridge bearings in all of the pivots, alloy pivot hardware, a longer rear shock stroke, post mount rear brake caliper tabs, and a low direct mount front derailleur. There are no ISCG tabs built in but that's become less of an issue with the advent of various thick-thin stepped chainrings now flooding the market.

Niner has added 20mm of travel to the revamped jet 9 but trimmed 110g, too, all while lending a slacker and more trail-friendly front-end geometry as well: niner has added 20mm of travel to the revamped jet 9 but trimmed 110g, too, all while lending a slacker and more trail-friendly front-end geometry as well
The new, lighter and bigger-travel Jet 9

Geometry receives some subtle tweaks as well. Notably, head tube angle has slackened a full degree to 71 degrees with a 100mm-travel fork or 70 degrees with a 120mm-travel one and reach has decreased just a few millimeters across the board. Seat tube angles are also now a constant 73 or 74 degrees across the board depending on fork travel. Bottom bracket drop is carried over from last year although curiously, the chain stays have grown slightly from 450mm to 454mm.

Shorter riders will be happy to see the addition of an extra-small size, too.

Retail price for the frame will be US$1,849 including a RockShox Monarch RT3 rear shock. Niner will also offer three complete builds, all with 2x10 drivetrains: the '4-Star' with a SRAM X0 drivetrain, RockShox SID XX fork and American Classic Race wheels for US$4,899; the '3-Star' with Shimano Deore XT, a RockShox SID RL and Stan's NoTubes Arch EX wheels for US$4,199; and the '2-Star' with Shimano Deore/SLX, a Fox 32 Float CTD Evolution fork and American Classic Terrain wheels for US$3,099.

All of the new JET 9s will be available around early September.

Brand new ROS 9 blends steel hardtail reflexes with a long-travel front end

Also coming from Niner this September is the new ROS 9 – a tough steel 29er hardtail designed for use with a 120mm or 140-travel fork and with a slack 67-degree or 68-degree head tube angle to match.

Niner builds the ROS 9 with a sturdier front end than its SIR 9 steel hardtail. Butted 4130 chromoly steel is used instead of the SIR 9's Reynolds 853 pipes, the diameter grows to 34.9mm throughout, and the 44mm tapered head tube is bolstered with a bigger gusset beneath the top tube.

Niner's new ros 9 is an aggressive chromoly steel hardtail with slack angles and designed for a 120-140mm travel fork: niner's new ros 9 is an aggressive chromoly steel hardtail with slack angles and designed for a 120-140mm travel fork
The steel ROS 9 frame weighs a claimed 2.77kg (6.1lb)

The differences become more pronounced as you move further back. A drastically curved seat tube and eccentric bottom bracket on the ROS 9 allows for effective chain stay lengths as short as 418mm (22mm shorter than the SIR 9) while still retaining multiple chainring compatibility and tire clearance for up to 2.35in rubber thanks to a clever bolt-on, high direct-mount front derailleur mount and a slick forged chain stay yoke. As Niner expects the ROS 9 to be used in a heavier-duty capacity than the SIR 9, there's even internal routing for a stealth-style dropper post.

Borrowed from the SIR 9 are the chain stays and seat stays, the forged 142x12mm thru-axle rear dropouts, and tidy post mount rear caliper tabs that are neatly tucked away inside the rear triangle.

Claimed frame weight is 2.77kg (6.1lb) without the eccentric bottom bracket insert or Maxle rear skewer. Retail price for the bare frame is US$899 and as with the JET 9, the ROS 9 will be offered in three complete builds: the '4-Star' with a SRAM X01 1x11 drivetrain, 130mm-travel RockShox Revelation RCT3 fork and Stan's NoTubes Arch EX wheels for US$3,799; the '2-Star' with a Truvativ AKA singlespeed drivetrain, 120mm-travel RockShox Revelation RCT3 fork and Stan's NoTubes Rapid wheels for US$2,899; and the more budget-friendly '1-Star' setup with a SRAM X5/X7 2x10 drivetrain, 130mm-travel RockShox Sektor RL fork and American Classic Terrain wheels for US$2,499.

James Huang

Technical Editor, US
James started as a roadie in 1990 with his high school team but switched to dirt in 1994 and has enjoyed both ever since. Anything that comes through his hands is bound to be taken apart, and those hands still sometimes smell like fork oil even though he retired from shop life in 2007. He prefers manual over automatic, fizzy over still, and the right way over the easy way.
  • Discipline: Mountain, road, cyclocross
  • Preferred Terrain: Up in the Colorado high-country where the singletrack is still single, the dirt is still brown, and the aspens are in full bloom. Also, those perfect stretches of pavement where the road snakes across the mountainside like an artist's paintbrush.
  • Beer of Choice: Mexican Coke
  • Location: Boulder, Colorado, USA

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