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.
Brown Tree Snake
a Cross Country Rider
Date Reviewed: February 28, 2013
Strengths: Ride quality very similar to titanium but at a fraction of the cost. The overall finished product is good and could use a more durable finish. The geometry fit me perfect and I really haven't even begun to tweak my position.
Weaknesses: The finish of the frame isn't bad and I know it's a mountain bike so it'll see it's fair share of rock dings and such but after my first ride there were small chips in the finish. Same thing happened on my Niner Air.
Insanely agile and super comfortable but a little on the heavy side. This bike handles as good as any of my other 29ers if not up there with the best.
Strengths: This is not your papa's steel. This frame is relatively light for a steel frame @ ~4.5lbs (2042g). Love the clean lines of a steel framed bike.
Weaknesses: Some might say the ebb, but I prefer this to sliders. This particular frame is set up with gears, so the ebb is a non-issue. No weakness that I can come up with and I have had this bike for almost a year now.
I always use to joke, Steel is real...real heavy! Not so much the case with the SIR 9.
Purchased this bike as a backup/wife's bike...built up geared (1x9) to be used by me on occasion in place of my lighter (stiffer) Scandium One 9. I was impressed that the frame was only ~1.2 lb (or ~540grams) more...what was amazing is how it felt on the trail. I took it to a familiar trail, very rooty, rocky, bumpy...it was noticably smoother, and with the components almost identical to the One 9, it was only ~2lbs heavier. Did I notice the weight? Sure I did, when picking it up to place on the car rack, I did not feel it on the trail...I thought maybe I did on the climbs, but that could be the placebo affect of knowing you are riding a bike 2lbs heavier than your normal ride. Love the bike and will certainly use it in the future where a geared bike makes more sense (like trails with steep, grainy climbs)...other than that, it will serve as my wife's main ride (glad we ride the same size bike). :)
This is my favourite frame so far. Running it singlespeed rigid at the moment, but have used a Reba fork on it as well. It is springy so you don't really need suspension, whips around singletrack and is responsive into turns. I know people have had problems with the EBB but I only experienced this on the first few rides. Then I tightened the EBB bolt more than recommended (being careful) and I have not had a problem since. Running the EBB in the 5-o'clock position on the drive side.
The only reason it loses a chili overall is on the price and paint job. It is an expensive frame here in the UK at £869 ($1400). The paint seems to wear away very quickly - it is soft and thin. But these are small factors when you have in your posession one of the best steel frames there is! No regrets in buying it.
Recommended to anyone serious about biking who will appreciate a top quality steel 29er frame.
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
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.
Similar Products Used: Vassago JabberWocky, Niner EMD, Niner AIR9
Bike Setup: Single speed fully rigid carbon fork and seat post
a Cross Country Rider
from Cambridge UK
Date Reviewed: April 5, 2012
Strengths: A mile eater, the most comfortable, most versatile frame I have ever owned. All day comfort, EBB, spot on Niner geometry, great cockpit position, nice to look at, gives a fluidity of riding joy (ahem).
Weaknesses: EBB can be a pain, paint chips easily (seems common with steel MTBs)
I love this bike, I really love this bike. I have done more 80-120 mile off road rides on this bike than any I have owned before. Due to carpel tunnel wrist problems I never thought I would be able to ride a ridged bike ever again & have not for the last 15 years....... until this frame, fork & the 29er wheels. It's not a race bike, it does flex a bit but that is why it is so nice to ride at other times. I also have an 11 speed Alfine hub, flow rim & dt rev spokes I sometimes use.... takes twenty minutes to swap it over. I have just done a three day mini epic across some rocky & some smooth hills carrying my gear & this bike just lapped it up giving superb grip on climbs & controllable speedy down hills. I also have an Air Nine carbon which with the tapered ridged forks is outrageously fast & has xc handling I have never experienced before (better than the sir), But........... if I had to get rid of one, it would be the Air carbon.
If you could only buy one bike....... buy this & book a respray for four years time !!
Similar Products Used: Kona unit 2-9, Niner Air Carbon, Salsa Mariachi, Spesh rock hopper 29, Omega TI custom 29er
Bike Setup: Medium root beer frame, ridged niner carbon forks (3k), ck rasta headset, hope front hub, crest rim, dt Revs & XTR 951 skewer. Rear wheel, CK ss hub, flow rim, dt revs, funn bolts, red Magura marta sl 160 front & rear, Hope BB, 2001 XTR 960 crankset (which was trimmed by myself with the aid of a junior hacksaw, electric file, emery cloth & a bottle of wine. Trimmed Salsa 25.4 pro moto carbon flat bars, Upside down 90mm x 7 degree ? carbon/alloy matrix stem, Ergon GX2 grips with bar ends, EC90 post, ti SDG formula fxr saddle
a Weekend Warrior
Date Reviewed: April 3, 2012
Strengths: Very comfortable, Light for steel, SingleSpeed or Geared option.
Weaknesses: Top Tube Frame Gusset is prone to rust prematurely.
Well, the user name says it all. I fell in love with this bike the first time I demo'ed one. It was set up as a Single Speed. I ended up ordering a Godzilla Green Medium frame and all the components to build a great rider/racer. I've switched back and forth between SS an geared quite a bit. So much so that I have two rear wheels built up for an easy swap. Currently it is running a 1x9 set up with X9 Twisty. Love the bike. Very fast and comfortable. Not as comfy as the Pugsley, but nothing is really.
Now for the bad. I have recently noticed a major design flaw with the way Niner installs the top tube gusset. It is not welded all the way around. (Or sealed). They rely on the paint to create the seal. But because this is where two radius-ed components meet (top tube and gusset) the paint does not always fill the gap between them. My frame has rust along the back edge of the gusset and you can begin to see bubbling about 1/4 inch from the edge. After I noticed my rust issue, I looked a a new bike in the showroom and sure enough, there was a visible gap between the gusset and the top tube where the paint left a "void". In the course of about 2 years, moisture has found its way into this void and started to rust the gusset significantly. The bike has never seen rain and is always stored inside. My thoughts on potential causes of moisture in this area would be sweat. Obviously a great deal of sweat finds it way to this area as it is directly below your head! When I purchased the bike I had it completely frame saved, but obviously this area was not reached as it is outside of the top tube.
I would recommend anyone who has a SIR 9 to keep an eye on this area. If you have a paint void, fill it now. If you have rust already developing, see if you can sand just the edge and apply paint/sealer, etc. If you have as bad of an issue as my gusset, well it may be pricey to fix. Since it is a major structural part of the frame, I am keeping a close eye on it.
I brought this to the attention of Niner (4/2/12 via the warranty e-mail), and have yet to hear their response. I know it has only been a day, but I will update the review once I hear their response. This is a good way to test their responsiveness to customer/product issues!
Similar Products Used: Karate Monkey, Pugsley, Stumpjumper
Bike Setup: Where would I even begin! Lots of goodies.
a Cross Country Rider
from Rome, GA, USA
Date Reviewed: March 21, 2012
Strengths: The 853 steel ride is very compliant, yet stiff enough to be a good climber. Sloping top tube gives a good amount of standover. The bike is flickable and a joy to ride. I have mine set up a singlespeed with the Niner carbon fork and I can't imagine running gears on this bike. I had some reservations about the ebb, but have had no issues thus far.
Weaknesses: Only weakness that I have encountered came when I was attempting to run a flat bar. The brake levers would hit the frame if turned far enough, which is likely to happen in a crash. This was easily remedied by switching over to a lo-rise riser bar, which is more comfortable anyway.
A great bike, especially for the steel aficionado. As a singlespeed, this bike has everything you could want. Niner's eccentric bottom bracket design is user friendly and does not slip. The quality of the welds and paint are unmatched, in my opinion. The frame is on par with independent builders for half of the price. The bike may very well make a great geared bike with a squishy fork, but I can't speak to that. You could find a lighter setup, if that is your number one concern. Overall, and especially as a singlespeed, this is a superior frame. I can also endorse the Niner carbon fork. Stiff, but tracks well. A good match for the steel frame.
Similar Products Used: Voodoo Nzumbi, Soma Groove, Surly Karate Monkey
Bike Setup: Kermit green Sir 9 with nude Niner carbon fork. Hope SS hubs on Stans Flow rims. Nothing fancy, but lots-o-fun.
a Weekend Warrior
Date Reviewed: February 12, 2012
Weaknesses: Weight (I'm nit picking because I'm a weight weenie)
I was very hesitant about buying the Niner SIR. Firstly, Niner frames cost a premium. Secondly, I've been a weight weenie for a very long time. Carbon frames are too fragile for me, steel frames are URGHHH HEAVY and Reynold's 953 frames are only affordable to me in my dreams. I finally bit the bullet and took a blind leap of faith. The ride quality is unmatched (Even my riding buddy on his Ti frame commented that he loved my bike's ride!), the geometry with Niner's carbon fork made it a match in heaven (Seriously, these 2 MUST be together to feel the magic). No regrets. Would probably buy another Niner but I still feel that their non R853 frames are overpriced. The SIR is a steel steal. Buy one before they up the prices on this one.
Strengths: Build quaility, geometry, paint and color choices, EBB system, Niner support
Weaknesses: Paint durability
This is by far the funnest bike to ride I have ever owned. It is a ridged steel single speed, so its not the fastest, but its pretty close. I have owned and raced it for the last year. During that time I have gone back and forth on running a suspension fork and the ridged. The recent addition of ergon grips has made the ridged fork much more enjoyable, so its going to stay ridged for the forseeable future. The ebb design and set up took some learning, but i pretty much have it on cruise control now and can change out gearing pretty quickly. With a 32t front im able to use the same chain for a 16t, 18t, and 20t rear. The ebb makes it possible to accommodate a wide range of gears with out ever removing the chain. With keeping an eye on weight, i was able to build my small to about 22lbs. Thats not to shaby for a steel frame. The frame is beautiful, tight welds and rich paint. My only grip is the paint chips way to easy. Niner must know this since they ship the frame with a small bottle of touch-up paint. Problem is the touch-up paint dosen't match all that well. Would love to see this frame in some of the new anodized colors since they are said to be much more durable. Bottom line is you cant go wrong with this bike. Run it as a ridged single speed one day, then a geared, front suspension racer the next. The bike can pretty much do it all.
Similar Products Used: Specalized stumpjumper comp HT, Specalized epic comp, Specalized stumpjumper FRS, GT 29r pro, Haro mary SS
Bike Setup: Single speed, matching ridged niner steel fork, carbon bars and steam, xt brakes, a-classic wheels and hubs, thompson seat post, stylo oct cranks, egg beater ss pedals, 2.25 rocket ron tires.
a Cross Country Rider
from Columbia, MD
Date Reviewed: January 22, 2012
Strengths: Supple ride
Weaknesses: None found yet
I love this bike - it's that simple. After riding the fantastic GF Rig SS for a year, I realized that my sensative knees (due to two cartilage surgeries) started to complain to me after about 20 miles of hard riding. As such, it was time to do two things; add some gears and seek more frame compliance. That, and because I can't own multiple bikes, I wanted a good all-arounder that also supported my SS jones. For me, the obvious choice was a SIR9. I had never ridden one, but knoew many locals with various Niner set ups.
Upon delivery, the frame was stunning. I've read some complaints about Niner paint jobs, but mine was excellent. I did get a price break because of the color - Solid Gold - but I will tell you with all the black bits on the bike it looks great. Further, after a solid year of riding the scratches I have are the same as I have had on any bike.
Where I live in MD, we have access to a huge cross section of trails that include everything from mild to wild - MD, VA and PA. The local club I belong to helps to maintain over 30 - and that's not even all of them! Anyway, suffice it to say, this bike has seen it all.
My set up is not weight-weenie, but is not bad. Before I swapped wheels and went tubless, the bike was 27lbs. My guess now is closer to 25, but I have not weighed it yet. When I go to lighter tires in the spring it will be even better....and I may try a rigid fork for a while too! yes, I use heavy brakes, but I bever have to bleed them, burp them or whatever else the ol' hydro's require.
The compact geometry of this frame allows for very quick handling - but not sketchy. It's rock solid in my book. At 5'-10", the medium frame is just right for me. The compliance is just right - not real noticable on hard sprints, but in rock gardens it gives me just the right amount of flex to help manipulate and pop the bike around. The climbing aspect has been great too. We all know or hear that 29er's climb well. Just know this bike confirms the claims. Running only a single 32T ring up front, I often wonder what insane climbs I could ease into should I add a 22 to the mix and explore the 2x!
Oh - one quick mention before closing..... the eccentric bottom bracket. Absolutely NO problems. In the 1x set up, it's set it and forget it, but know that this bike has seen miles of stream crossings, dirt and dust and it has never been a problem. I believe that Niner has the whole BB thing spot on.
That said, buy this bike with confidence. As far as steel frames go, it's priced right in the middle of many excellent options out there. Make this your choice or the MCR version and I don't think you'll be disappointed. Ride on.
Similar Products Used: specialized stumpjumper 29 HT
Bike Setup: SS, Reba race fork.
a Weekend Warrior
from South Florida
Date Reviewed: July 19, 2011
Strengths: Fantastic geometry. Smooths out roots and rocks something serious. Lightweight for Steel frame. EBB and changeable dropouts to convert to geared or SS. Rides like a dream!
Weaknesses: None so far.
After getting beatup on my hardtail 26" Kona Cinder Cone, I was ready to move up to a full suspension bike for our rocky, rooty singletrack courses in south Florida. I then took my friend's Diamondback Overdrive 29er for a lap (while drinking the Kool Aid) and realized I too needed to upgrade to a 29er.
I got a good deal on the frame and rigid fork, so I built the bike with the rigid while I save my money for a squishy fork. This bike rides so nice with a rigid fork, I have no reason to upgrade anytime soon. It rides way smoother than my 26" hardtail did. I can only imagine how smooth it would be with a Fox on the front.
Anyone looking for an awesome Hardtail or Rigid 29er need not look farther than the Niner SIR!
Similar Products Used: Diamondback Overdrive is the only other 29er I've ridden.
Bike Setup: Rigid Niner fork. 1 x 10 Shimano XT.
a Cross Country Rider
from NC, USA
Date Reviewed: June 15, 2011
Strengths: Ride feel. Don't believe all the hype that this is like a full suspension ride - it certainly is not. However- being realistic, the ride quality is certainly smooth as can be for a hard tail. Coming from riding fisher and bianchi aluminum 29ers and 26ers, this is a TREMENDOUS upgrade in ride quality. Definitely leaves me less fatigued.
Weaknesses: BB design is okay. I know there are alot of complaints about it out there, but there are also many of us who if we take the time to set it up right the first time and maintain regularly - it works like a charm. It doesn't take a whole lot of grit/dirt to start some slippage - if you notice slippage - pull it apart, clean throughly with rubbing alcohol and reassemble - it will then work as advertised
Super smooth steel frame with great all around geometry for all day adventure. If you are looking for the racing rocket - look elsewhere.
from Winston Salem NC
Date Reviewed: May 16, 2011
Strengths: Light Steel, Cheapish Nice colors Bout it tho..
Weaknesses: This is one dead feeling FLEXXY steel frame for a 155 pound 6 foot rider.. Creak Clicjk Creak Click Creak Click Creak Click EBB.. Shop A no help.. Niner Cust service No help..Shop B no help Shop Genius and Bontrager field tester No Help. Niner says Put EBB in dry.. No grease... Shop guys say they had major creak issues till they greased their bikes..So me no get it?? Low pedal clearance.. EBB needs a barrel nut installed in cup to prevent stripping out bolt hole.Compared to other steel 853 frames this was slow side to side - dead feeling with very little trail feel. Niner Customer Support was less than helpful.
She is going on E Bay. I don't ride with headphones and I can't deal with the creaking.. Flexxxy out of saddle efforts work everything lose in the BB area. If you are a trail rider and NOT a racer this will do ya fine.. Wanna get frisky with it.. Get a real frame.
Similar Products Used: Kona Unit Gunnar Rockhound Gunnar Ruffian Trek / Fisher Superfly Kona Kula Deluxe Lynskey Ridgeline
Bike Setup: Singlespeed, Reba 29er, Avid Juicy 7 Carbon, Thomson bits Stylo cranks King BB and King SS Wheels 22.5 pounds Full hardtail race..
a Cross Country Rider
from Boise, ID
Date Reviewed: April 28, 2011
Strengths: Absorbs trail well, responds very quickly on quick turns, very nice steel!
Weaknesses: none so far
This is a real step up from the sanko steel on the redline. A bit stiffer (laterally) but so much more responsive. Still has the softness of steel over small bumps. I have over a dozen rides on this bike and loved every minute.
Bike Setup: Stans crest wheelset, Chris King hubs, avid juicy brakes, truvative stylo crank, chris king headset, thomson post, wtb rocket seat, easton carbon bar, rockshock reba fork, CB pedals. weighs in at 24.5 lbs.
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 »
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 »
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 »
Well, the biking bug has bitten me again HARD. Went from having no bikes two weeks ago to two bikes now (one in my possession, one with build parts on the way).
Anyway, ordered a Motobecane Fantom 29Pro, was fairly happy with it but found it a wee bit small, so that one is getting passed down to ... Read More »
I'm looking for the lowest stack height headset that works with a S.I.R.9. Does anyone have any knowledge on this? The FSA, Cane Creek, etc. all have so many options, it starts to get confusing very fast.Read More »