Prices shown in currencies other than USA Dollars are estimates based on current exchange rates. We will charge your credit card in USA Dollars on the day your order is shipped, and the conversion to your local currency will be done at the prevailing rate by your credit card issuer.
Shipments outside the USA are declared as “bike parts” for customs purposes and will include the actual amount paid for merchandise and shipping. Jenson USA will not mark your parcel as a “gift”, declare a value lower than the actual price paid, or otherwise prepare false customs information.
Note: Photos are for illustration purposes. You will be shipped a complete bike with the specifications listed below.
Niner SIR 9 2 Star Single Speed Bike
The Niner SIR 9 demonstrates steel is real! Steel bikes are as relevant today as they were 50 years ago. With that said, all steel is NOT created equal. The Niner SIR tubing is a custom selected set that utilizes the best tube options for each application within the frame. The front triangle is comprised of new Reynolds 853 DZB (Double Zone Butting) tubing. Developed for mountain bikes, more specifically 29ers, Reynolds 853 DZB offers two significant advantages. Historically downtube fork clearance on 29ers has been tricky because of the relatively high head tube to bottom bracket height. A straight downtube needs to be welded high on the back of the headtube to achieve fork clearance, often requiring either a gusset between the headtube and the downtube or a thicker heavier downtube to achieve the desired strength. The Reynolds 853 DZB tube overcomes this limitation by incorporating two different butting profiles on the same downtube. The superior strength is combined with a butting profile in the rest of the tube that maintains ride quality, and keeps the weight down. Secondly, the 853 DBZ tube is the proprietary bend. Niner worked with Reynolds to shape the tube for the SIR 9 so the tube can attach lower on the headtube, which reduces front end torsional flex, and increases steering precision, while adding strength.
Like the rest of Niner's bikes, the SIR 9 utilizes Niner's tried and true geometry. There are plenty of nifty features that you’ll find in the SIR 9. The Niner SIR 9 features the BioCentric bottom bracket system. The BioCentric makes adjustment easy across a wide range of gears and eliminates the need for adjustable dropouts, giving the cleanest possible solution for singlespeed use. The BioCentric offsets the bottom bracket spindle 8.5mm from center, offering greater range of adjustment compared to a more traditional EBB setup. Conventional EBB units mounted with set screws that can become tricky to finely adjust over time, or expansion wedges that can warp the bottom bracket shell of the frame, while split BB shells that clamp an EBB can stretch or ovalize. The BioCentric II shuns these quandaries by using two bolts to apply a clamping force on the outside edges of the BB shell, eliminating the likelihood of ovalizing or indexing the shell itself. The BioCentric II will certainly have you seeing singlespeed living in a whole new light.
Highlighting the Niner SIR 9 2 Star Single Speed build is Niner’s Cogalicious Single Speed Cog. Constructed from 7075 T-C aluminum, the Cogalicious reflects Niner’s dedication to bring quality to those who are seduced by the suffering that comes from having but only one gear. The Cogalicious is slightly offset so you can fine tune your chainline by flipping the cog, while the thick offset base prevents the damage of alloy freehub bodies under heavy loads. The Truvativ AKA cranks feature OCT hollow forged arms, keeping weight to a bear minimum without sacrificing strength and stiffness. Speaking of stiffness, The Niner RDO rigid carbon fork mates perfectly with Rock Shox’s 15mm Maxle for race-dominating power transfer and vibration dampening. Stan’s No Tubes and Schwalbe combine forces to offer a tubeless wheel set up that can corner, accelerate and climb. SRAM Elixir 5 brakes and brake levers inspire confidence in your braking to keep you descending like a sinned soul. Niner components rounds out the cockpit with a carbon seatpost and an alloy bar and stem. Not to mention, the ultra flashy head badge and dazzling paint is enough to make you swoon.
2014 Niner SIR 9 Frame Features
73mm BB width (with BioCentric installed)
BioCentric is compatible with external bearing cranksets only
27.2mm seat post size, 400mm length recommended
28.6mm front derailleur, high mount, bottom pull
29.6mm seat collar size
Tapered headset with internal (ZS) top cup and 1.5" external bottom cup. Cane Creek standard description: ZS44/28.6 | EC44/40
Small frame has one bottle mount inside the front triangle. Medium, large and XL have two bottle mounts inside the front triangle
Replaceable derailleur hanger or SS insert
12 x 142mm Maxle rear spacing
Can fit up to a 2.4” tire (tire size varies by brand, some tires may not fit)
Niner head badge
Niner RDO Fork, 15MM
NOTUBES 3.30 SS/RAPID, 15MM FRONT, 142 X 12MM Rear
Schwalbe Rapid Rob EVO TL 2.40/Racing Ralph EVO
SRAM Elixir 5 with 180/160MM G2 Rotors
SRAM Elixir 5
Truvativ AKA, 32T
Niner Cogalicious 20T
SRAM PC 1
NINER Flat Top Alloy, 710MM, Red Niner
NINER Alloy Stem, Red Niner Graphic
WTB Volt Race with Cr-Mo Rails, Niner Graphic
NINER Carbon Seat Post, 400MM, Red Niner Graphic
Note: Components are subject to change without notice.
Effective Top Tube Length
Seat Tube Length
Head Tube Length
Jenson USA ships worldwide, including APO/FPO addresses. For a quote, simply add the items you are interested in to your shopping cart and look for the "Shipping Options" box. You don't have to login or create an account to see shipping charges.
Some manufacturers restrict where we can ship their products. If this item has shipping restrictions, they are listed below. If you'd like to buy an item that we cannot ship to your preferred address, we can accept your foreign credit card and ship to a USA address for you.
Get free shipping with your $50 purchase today when you choose Standard Shipping at checkout. Please note this offer is only available to physical shipping addresses in the 48 continental United States (no PO Boxes), and oversize charges still apply on some heavy/large items
Due to manufacturer restrictions, this product cannot be shipped to the following locations: