Niner Singlespeed Hardtail Frames

The ultimate 29er hardtail. The Air 9 Carbon features Bio-Centric EBB technology and CYA Bottom Bracket system – the most flexible BB/gearing system available. Run your Niner singlespeed or geared or take advantage of several BB inserts to accommodate your choice of bottom bracket technologies, including the new BB-30 standard.

Frame development began with reams of testing data, which helped Niner to determine the primary tube shape. Finite Element Analysis studies, physical mock-ups, years of experience and a rigorous industrial design phase have all contributed to this extraordinary design. Every decision, every shape and every tube has its origin in a design parameter that requires the Air 9 Carbon to hit very specific targets for stiffness and strength in all three planes. Key sections such as the downtube and bottom bracket area have received massive structural shaping to increase torsional rigidity and the swooping lines and angles of the Air 9 Carbon are functionally beautiful before they are aesthetically pleasing. All these features help to disperse energy, avoid stress risers and increase the natural damping characteristics of the material.

The One 9 is the lightest production 29er single speed frame on the market. Made with the same custom drawn Easton GX2 Scandium as its geared brother, the One 9 delivers high performance through advanced tubing and tubing manipulation. From the outset, the One 9 had seemingly simple design objective: create the best-riding single speed possible. This meant a blazing fast frame, with no discernible flex at the bottom bracket or through to the rear wheel without creating an overly harsh ride. Working directly with Easton on the tube set to create a frame that did exactly what they were after: a fast, nimble, but comfortable ride.

In addition to the front triangle, the rear s-bend chain stays and seat stays do more than look good. The tubing has been shaped for maximum horizontal stiffness while still allowing for some vertical compliance. Rounding out the package is Niner’s own super light eccentric bottom bracket, allowing for easy wheel removal with the disc brake and versatility in EBB positions (high or low) to tune your ride for your terrain and riding style.

The One 9 fuses the most technically advanced tube set on the market with the simplicity of a single speed and proven Niner geometry to give you a completely fresh riding experience. No chain chatter, no gears, just pure, unadulterated fun.

The S.I.R. 9 is the most versatile bike in the Niner stable, fusing the “steel is real” feel of Reynolds tubing with the ability to run the frame as either a geared bike or single speed. The S.I.R. 9 uses the same custom drawn Reynolds 853 tubing as the M.C.R. 9 and combines it with Niner’s ultra-light eccentric bottom bracket. Custom “breezer” style forged dropouts have a replaceable alloy derailleur hanger and come with an insert piece for running the bike as a single speed to eliminate the unnecessary derailleur hanger for a clean look.

Niner’s own EBB, at 100 grams, is the lightest eccentric bottom bracket on the market. In addition to being light, it’s extremely functional. The EBB has more swing than any other EBB, over a full link, so you will never have to hunt down a half link to get correct chain tension and vertical dropouts mean you’ll never have to mess with the disc brake to remove the wheel.

The S.I.R. 9 is truly a do-everything frame. Run it single speed at your local race, then convert it to a full gear set to do the Trans-Alp. Want a 1 x 9? No problem. Or, if you’re just not sure, the S.I.R. 9 will give you the option of trying it all.