Niner Bikes S.I.R. 9 29er Hardtail

4.8/5 (65 Reviews)
MSRP : $999.00

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Product Description

The S.I.R. 9 is the most versatile bike in the Niner stable, fusing the ?steel is real? feel of a new Reynolds 853 DZB tubeset with the ability to run the frame as either a geared bike or single speed with Niner?s ultra-light eccentric bottom bracket. New BIO-CENTRIC II BOTTOM BRACKET SYSTEM! The Niner Bio-Centric 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 adjustments with gear changes. While tubing upgrades are the focus of this new design, Niner has not forgotten the details. The new the S.I.R. 9 uses 142x12mm spacing with an included Maxle for added rear-end torsional stiffness, removable downtube cable guides, post mount brake bosses between the chain and seatstay for braking precision and, of course, the Niner headbadge and two great color options for that finishing touch. 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 10? No problem. Or, if you?re just not sure, the S.I.R. 9 will give you the option of trying it all. Features: -Sizes: S, M, L, XL -Available Colors: Hot Tamale and Arctic White -Custom-bent double-butted Reynolds 853 DZB downtube. -44mm Reynolds 631 head tube allows use of tapered or 1?1/8? forks. -Compatible with a rigid or 80 - 100mm travel suspension forks. -Niner Bio-Centric II Bottom bracket system and removable downtube cable stops for clean singlespeed or geared setup. -44mm head tube compatible with tapered steerer forks. -Rear Hub Spacing: 142mm x 12mm (Maxle axle included with frame) -Up to 2.4" rear tire clearance. Please note that if you are interested in a single speed specific build, please contact the Wrench Science Niner specialist.

User Reviews

Overall Rating:5
Value Rating:4
Submitted by rob1208lv a Cross Country Rider

Date Reviewed: May 3, 2012

Strengths:    strong, a work of art, easy to change from gears to SS

Weaknesses:    kind of heavy (but its steel), EBB can be a pain sometimes, little pricey

Bottom Line:   
I currently have mine set up SS. After the first ride my EEB came loose, I followed all the recommended install instructions and haven't had a problem sense. I was riding a Jabberwocky prior, that bike was stable, but the SIR9 is easier to throw around on switchbacks and the steel feels more plush, and nimble, Plus I could never run gears on my Jabber for bike packing. I also Had a Niner AIR9 that bike was fast, but it bounced me around all over the place, I prefer the Steel. The Niners Geo seems to fit me the best.

Expand full review >>

Favorite Trail:   goosberry mesa

Price Paid:    $500.00

Purchased At:   Las Vegas Cyclery

Similar Products Used:   Vassago JabberWocky, Niner EMD, Niner AIR9

Bike Setup:   Single speed fully rigid carbon fork and seat post

S.I.R. 9 / Niner Headset Assembaly Question...

I have a Niner headset (shown in picture) and feel that I installed it correctly however there's the slightest gap thats created by the compression ring... is that supposed to be there? I'm holding off cutting the forks until i get this figured out... thanks for anyone that can provide some insight! ... Read More »

Niner S.I.R 9 vs One 9 RDO?

The previously mentioned bikes are on my shortlist for my new single speed. Has anyone had experience with either of these bikes? Good or Bad? Any idea on stock weights? Sorry if this subject has been beaten to death but the Almighty Google is giving me nothing. [url=] ... Read More »

New S.I.R. 9 - IMBA Limited Edition Auction starts tonight!

Want the new S.I.R. 9 with 44mm head tube and 142x12 spacing? Want one of 6 that we have had painted for our IMBA benefit? The auction starts tonight - as soon as it is live we will post the link here and on our Facebook page. 100% of auction proceeds from this brand new product launch go to IMB ... Read More »

Niner S.I.R. 9 - First SS, First Build

So my first real post on mtbr, taken me a while, need to stop being such a lurker. (My first 5 were so I could post this in the SS forum, rather than general). I want to build a SS 29er, I've got some idea of the kind of bike I want, and I have the money (or will as I buy components) to put it t ... Read More »

Niner S.I.R. 9 Opinions

Hey guys what do you think of the Bio-Centric BB system? I am pretty much at wit's end for the ideal steel bike for SS and geared platform. I go either a Niner or something else. A bike I can race with but have fun with a SS, it must be steel or ti. A bike frame to end it all.Read More »

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