On Test: Specialized Stumpjumper Carbon 29 SS- by Grannygear
I have been on a high end steel single speed in the Spot Rocker SS (and many other very respectable steel frames like the OS Blackbuck) and I have been a full season on the Specialized Carve Pro SS, a very nice example of hydroformed aluminum with a shot at building compliance into the frame’s design. I also just got off a very fine example of Ti as a singlespeed frame material in the Spot Rocker SS Ti. But I have danced around carbon fiber as a material for a hard tail frame, having some brief rides here and there and some time on a Breezer carbon bike with gears, but I never have been on a carbon fiber single speed. Now you may say that there is no real single speed specific design or special singlespeed geometry that any decent hard tail frame does not already have and you may be right. But the demands of single speeding are a bit unique. You stand. A lot. And when doing that, you often pedal hard. Even harder. So there is a need for a stiff bottom bracket area. I think a shortish (17.5″ or under) chain stay length is best for keeping that rear tire hooked up and driving when you are out of the saddle and leaning forward. Then the main triangle, perhaps the top tube most of all, needs to be tough too as there is so much leverage imparted into the frame from typically very wide handlebars. Better-than-good tire clearance is welcome as many single speed riders run a fattish tire for comfort and performance at lower pressures.
So, when I rode the S Works Stumpjumper at the 2013 Specialized Global Press Launch this past year in Utah, I was taken by how smooth riding the bike was. Of course it was light and had chi-chi carbon wheels, etc, but a good deal of that experience had to be from that FACT IS 11m frame that all those nice parts were bolted to. Then, in the display area of the Expo Tents, I saw a single speed frame done in carbon with a Stumpjumper decal on it. Not a new 2013 model, but carried over from 2012, the understated graphics and single speed specific features called to me. It is a half step below the S Works level frames, being FACT IS 8M rather than 11m construction, but there is no S Works version of a stand alone single speed frame set.
So soon we will be building up a 2013 Specialized Stumpjumper Carbon 29 SS. Stay tuned as I jump into a high end composite frame built up with some very good components and hit the hills. We also will be talking to one of the engineers at Specialized about the tech in the FACT IS 8m carbon frame and how composites are developing and being refined for bike frames.
See ya soon.
Note: Specialized sent over the Stumpjumper Carbon 29 SS for test/review at no charge to Twenty Nine Inches. We are not being bribed, nor paid for this review. We will strive to give or honest thoughts and opinions throughout
I’d love to hear from the Specialized engineer how recent improvements in software for composite structural simulation have helped design frames like this.
For Specialized to produce something quite unique like this frame is very unique in itself.
It allows us tinkerers to build something feather light as an SS. Good on the big manufacturers who still make niche stuff like this. Liking this as the Pivot Less and of course everyones favorite Niner air 9 C a LOT !
I would definitely try this SS frame if I could afford it, really nice one!
What about the cheaper alternatives, like On-One Lurcher which has changeable dropouts/swapout? Despite of the decent price for a carbon frame (814 USD+shipping) the only downside is the weight which is (much?) higher than usual. I would see a test here with a Lurcher frame as well!
@Motivated…well, I will try to do justice to your question during the interview.
@Professed…Yes, it is unique in that way. In fact, I wonder how many they actually sell? It is interesting talking to industry folks about SS specific parts like hubs, wheels, frames, etc. The general consensus is that it is so niche that hardly anyone wants to deal with it. The sales numbers are not there. In a way, that lets SS be a boon to the smaller builders/vendors that can supply the crazies like GT and I with single minded pursuits! So yes, it is a rare bird in that a major player is offering this.
@Smh…We will ask about the Lurcher. This XL Stumpy frame weighs 1600g with seat post clamp and of course, the sliders in place and 4xWB screws. The weight stated on the On One site for a Lurcher is “approx 1550g”. I am assuming the standard practice of weighing a Medium size and I have no idea, but I assume they weighed it with the lightest drop-outs on it. SO, it does not look like the Lurcher is “(much) higher than usual” unless the Stumpy is as well. Niner does not publish weights, but a bit of internet cruising seemed to point to weights that are right in this range too for an AIR9c.
Just as an aside, I would never shop for a carbon frame based on the lightest weight.
gg
“many single speed riders run a fattish tire”
I fail to see the correlation.
@Scott…? Well, the SS riders seem to gravitate toward a larger volume tire and at a lower pressure for comfort/performance. If you are a hard tail XC racer type, not so much. Just a different dynamic that I have noticed over time. the same goes for Alt bars, odd grips, etc. SS riders seem to follow function over form.
As well, if the weather is junk, then I grab the SS and mud clearance becomes more important too.
gg
very interested in finding out if the bb interface causes you any trouble as i’ve had issues with PF30
@Fixie Dave…well, in this case I used a PF30 to GPX adapter that had been trouble free in the Salsa Spearfish frame. I do not expect any issues, but we shall see.
gg
Nice one. But not for german bikers, thanks Specialized … very sad and out of all reason
GG: looking forward to this build and reviews,this is my Dream SS frame. I have the new Salsa El Mar.SS and love it,but a carbon lt. wt. SS would be cool.
This will be interesting as I am building an Air9 CVA (formerly Air9 Carbon)as we speak which I would think would be the main competitor for this frame. By the way, my Medium weighed 1199 with just the frame which to me wasn’t that light, but my frame looks massive in the right places. I guess the light Niner is the Air9 RDO which is under 1000 I have heard and probably not nearly as stiff. (Even though it is not a SS frame, I was considering it since I could use a Beer Components ss adapter in its PF30 bb and probably save around 300 grams because the Beer adapter is probably lighter than the Biocentric which has to fill a larger hole.)
This Spec frame also looks to be massive in the right places. This is the first thing from Spec to catch my eye in a while. I even like the graphics.
My current SS’s are a One9 with Fox and a Sir9 full rigid. And I rode them combined over 2500 miles this year of my 5000 total miles and at the rate I am going SS will probably be 60% of my riding next year. If I remember correctly my One9 frame was only a little over 1200 grams so almost the same weight, but obviously not as stiff especially in the head tube because it is not tapered and not nearly as massive.
Regarding the Fat Tires issue. I am one of those SS’ers that insist on relatively fat tires at relatively low pressure (tubeless for sure) because it just seems to work so much better for SS. Maybe it has to do with carrying speed, etc. I don’t know why; I have lots of wheelsets and lots of bikes and I have tried many many combinations, but that is what I want on my SS. All my SS’s have 2.3 or 2.2′s at all locations and all those tires as mounted are at least 2.2.
Niner has the frame only Air 9 RDO listed at 1125gr. The Stumpy is a pig at 1600gr!
@Peter Fall….from the Niner website: “Is it lighter than the Air 9 Carbon? Yes, quite a bit. The Air 9 RDO averages 1125g in a Medium frame (without seat collar or protective downtube tape).”
So this is a Medium sized RDO frame with no seat collar, no protective wrap, and no sliders.
The Stumpy is an XL frame and I weighed it with the protective tape, seat collar, and sliders/bolts, etc.
Now that we have that clear, the Niner RDO may still be lighter than the Stumpy. A better comparison would be the Specialized S Works Carbon 29 frame set and I have no weights for that. Wanna’ bet it is lighter than the SS non-S Works frame I have?
Weight is not everything but it is one thing.
gg
…as well, the cost of the S Works frame is higher, before that gets mentioned, but that is what, a $1000.00 fork and a $100.00 seat post?
That Niner RDO frame is a sweet looking beast, but I think when you get it all equal that the Carbon SS is hardly a pig.
If it is, then pigs do indeed, fly.
gg
Post Scriptum…weight of an S Works carbon Stumpjumper frame, no collar, no dropout…bare nekkid…averaged over three medium sized (17.5″) production samples with applicable paint, decals, etc. : 1092g
Ahhh…perspective. And it really points to this…the real players in this game are all balancing out the same parameters of weight vs. cost vs. strength vs. longevity vs. function vs. whatever. And, despite all the marketing spin to the contrary, I doubt that any one company has a huge advantage in design, construction, technique, etc. when it comes to carbon frames. The guys who are doing this well are all making very good bikes for the intended purpose.
gg