S-Works Shiv Disc

In 1990 or thereabouts Chet Kyle, Steve Hed, John Cobb and others were habitues of the wind tunnel at Texas A&M University. I was a bike maker, I pretty much got along with everybody, and so I was allowed to glom onto the testing.

Steve Hed was precociously curious, whether about wheels or just anything related to bikes (and not limited to bikes!). Among other things he’d take wheels, frames, forks, and just swap stuff around. One discovery he made, according to him: Aero benefit follows the fork at least as much as it follows the frame. He moved Lotus, Hooker and other forks from bike to bike and certain forks made mortal frames fast. One of the faster forks was the old Schwinn Ashtabula, so-named because it came out of Schwinn’s factory in Ashtabula, Ohio. (You could anchor your boat with it, but it was pretty fast.) Another very interesting – curious looking but very fast – fork came on models made by Seattle custom bike maker Dan Wynn.

This fork had blades that were spaced at 100mm axle width – as most forks then and now – but they remained spaced to 100mm all the way to the fork crown. You can’t imagine how strange this looks and I regret I don’t have a picture. Why did this fork test fast?

Space. The air had plenty of space between the blades to find its way around the wheel, and likewise each blade. No interference drag, such as is common on bicycle front-ends. I’m no genius, but I’m no idiot either. I designed a fork of my own, called the Illuminero and its successor, the Carbonaero, and placed these on my Quintana Roo Bikes. The blades were far from the wheel, but not as far apart as in Wynn’s fork. I made up the difference by moving the wheel away from the blades. I had Steve Hed make me hubs that had a 55mm or 60mm flange spacing (as opposed to the usual 80mm). The spoke triangulation (lenticulation) was plenty fine because the rims were deeper (the spokes were very short – just over 200mm long).

I wondered when anyone would actually catch onto this. No one did. Until 2009, almost 2 decades later. Felt’s Dave Koesel (Superdave on our reader forum) showed me the new Felt tri bike front ends. You can’t keep a good idea down.

Superdave now works for Specialized. Coincidence? I don’t know. Felt’s new Shiv Disc is not a Dave Koesel project. In any case, Specialized has exploited the move to disc brakes in a more thorough and, to me, obvious way than anyone has, at least in what the fork should look like.

I have some problems with this bike, which I’ll get to. But the bike is ground breaking. Let’s talk about it.

The Fork

Could you have made this fork with a rim brake? Maybe. Sort of. But Specialized thought wildly outside of convention. I don’t know all of what it had in mind. Specialized says the fork is a handling play. Handling in crosswinds. Steering torque and all of that. You have to ride it to feel it. Okay.

But I didn’t ride it, so I don’t know. Just, this style of fork making ought to be a clear aerodynamic winner. As you’ll see, the fork is very deep, it stays wide as it travels up to meet the frame, and where the clearance is quite (appropriately) tight is at the top of the tire, where it greets the bottom of the frame’s nose cone.

What I’d rather have seen was the aero section sit behind the steering axis (or more behind), or at least to have seen that modeled, to see if it counteracted the torque on the steering when you’re hit with a side wind. But this would clash with a frame design element, which is the continuation of that blade all the way up to the pursuit bar. If you extend that blade further back than it is then the back of the blade hits the frame when you turn the handlebar. Couldn’t you hog out some of the trailing edge of that blade as it gets above the crown area so that you get more clearance for turning? I’m sympathetic to Specialized. They’ve done a really nice job with this bike and they don’t need me asking for more and more testing on unproven notions. Maybe after I ride this bike I’ll stand down and acknowledge that what I’m asking for is not needed.

There is a mono-pedestal and this is a *thing* now in the newer, better tri bikes. Trek started it with the 2014 Speed Concept, Cervelo continued it with the P5X (likewise TriRig with its Alpha One. The nice thing about this bar – according to what Specialized told me – is that the bolts come down from the top, it’s very easy to change the bolts and pedestals for shipping or to simply change your pad height. This seems much easier to change than the Speed Concept’s pedestal.

Both the mono pedestal and the folding pursuit bar (like a plane on an aircraft carrier, just, these “wings” fold down) are great ideas, both when the P5X was unveiled in Kona and now with this bike. This bike’s mono-pedestal has 115mm of rise to it, and here’s another trend with Canyon’s Speedmaxes, the P5X and now this bike: low-slung front ends that are able to pedestal quite high. When you do offer this much pedestaling you’ve got to offer multiple pursuit bar heights and this bike has 3.

The other similarity between this bike and the P5X (besides the price tag) is the attention paid to carry-aboards. Cervelo and Specialized are two serious companies, with data driven thinkers, and at some point you come to some obvious conclusions once you exhaust all other options: Bikes diverge greatly in their aero performance as the rider starts to tape and strap things to his bike. Remember, I started the Kona Bike Survey and ran it for the first 15 years. I’ve seen your habits. Some of your bikes are loaded up like the Clampett family truck. It got to be so that the low hanging fruit left in bike design was just in where to put everything that dirtied up your bike. Hence the P5X, the Diamondback Andean and this new Shiv Disc.

Specialized is saying that this is what the bike should look like; let’s rethink where the food, spares and fluid should go based on the bike we now have.


Specialized and Diamondback both figured out the same thing: If you want the perfect splitter in back, it’s got to be skinny – so skinny it makes a pretty bad storage area for spares. So Diamondback gave you an almost useless storage area (no problem, because it’s got plenty of other great storage) and Specialized decided the fluid should go there. It carries 1.5 liters. Is it refillable on the fly? I think so. But I don’t know that refilling it on the fly is a great idea (I’d have to try it before I recommend it). My intuition tells me that you should just run what ya brung back there. I like the idea of a cold pack or two in that reservoir; throw those in. But I don’t know; I haven’t tried it.

Specialized said, “You know what? The down tube is a pretty useless tube to try to make aero.” I think they figured out with the latest Venge that the Tarmac down tube was really pretty good all along, and the Venge down tube got kind of Tarmacky. They stuck what they learned about down tubes and low slung seat stays in the new Shiv. Why not? But that meant that the down tube is sufficiently big so they could cut a hole in the top and put food in there. I think that’s brilliant. Just, it took gravel biking before the road bike motif inherited what triathletes knew was a great idea all along: Put your food on the bike (in a Bento) rather than in your jersey pocket. Will Specialized put down tube storage on a road bike? That would be bold.

Because of disc brakes, and the fork design, tire clearance is not a problem. I looked over Tim Don’s Kona bike and he was riding 26mm Turbo Cottons, which measure more than 26mm (I think that tire is probably as wide as some other tire makers’ 28mm tires).

Fit & Geometry

Below is a cut and paste of the geometry chart of this bike throughout the size run, because I’m really only interested in the rows that I’m displaying and I have a few notes in my markup.

This bike comes in 4 sizes as you see. The Speed Concept has an XL. I’m size L in that bike, which has a reach of 425mm and a front center of something like 625mm as I recall. Look at this bike, you’ll see that the L is really an L. So, if you’re an XL, it’s not that this bike’s L is your size. There just isn’t an XL. That’s a size yet to be made.

Remember, Quintana Roo’s size 54cm in its PR series, Felt’s size 56cm, Dimond’s size M, are also all this same size. Canyon’s Speedmax in size M has a reach of 435mm compared to this bikes 421mm in size L. Yes, that means this new Shiv in size M is actually larger in both height and length than a Speedmax in size L. (There I go, using that pesky math again! And facts!) Bear this in mind when you’re choosing your bike.

That doesn’t mean this isn’t a great bike and that it isn’t geometrically correct. Just that there’s no big bike size here. If you’re taller than 6’3” this bike starts to get a little short in the front/center for you. Further, because the L really isn’t all that L, I’d have been happier with 170mm cranks. But that’s a small point. That 2.5mm wouldn’t keep me from buying the bike.

My Long Running Disagreement with Specialized Tri Bikes in Size XS

My larger issue is with the smaller size and I just have a long running difference of opinion with Specialized over this. See that 68mm trail on the XS? That’s a lot of trail. Meanwhile, the 57mm of trail in the S isn’t very much. This is the M.O. with Specialized and its XS tri bikes. It won’t make the bikes with 650c wheels (almost no one will these days), so as you see the reach changes a bunch between the S and the XS, but not the stack (you can only make a bike so low with 700c wheels).

Specialized won’t make the bike with a lower trail number or a smaller front/center (BB to front wheel axle). I would prefer the XS to have a front/center more like 565mm (which it could do because it’s spec’ing a 165mm crank), it needs a steeper head angle, and a fork with more offset (like, 55mm). but that would mean yet another fork mold you might say. Maybe. Or, maybe just another thru axle placement.

I have no quarrel with the meat of the size run: S, M and L. They appear to me soundly designed, both for fit and handling. My issue is with the XS, which I'd have made slightly differently, and the XL, which doesn't yet exist.

If they have a Pad Stack/Reach prescriber I haven't seen it. They need one, and they need to put it on the website.

Price & Delivery

It’s coming in April. Launches happen best when they happen commensurate with that bike’s availability. Everybody knows that. Specialized knows that. They just got caught in between cycles. You can’t ask Javi Gomez, Sarah True and Lucy Charles to ride bikes designed almost a decade ago in the World Championship. So, this bike is either a half-year late or a half-year early. Stuff happens.

This is a $14,000 bike, comes with its own case, comes with Dura Ace Di2, top cabin all the way. Yes, I know there’s going to be wailing and gnashing of teeth over the price. Just like with the P5X. Can you and I work through this? I buy most of my stuff just like you do (because if I accept free bikes, race entries, run shoes, whatever, then I’m obligated and I don’t want to be). So, you and I, we’re in the same boat. I don’t get offended by a $14,000 or $15,000 bike because the downstream, downspec version is coming.

These $12,000 and $15,000 halo bikes are about to spawn more affordable babies. This bike that you see here is not made for you and me. It’s made for the pro athletes, though versions will be offered to you. I love this bike. But I’m not going to buy this bike, because I can’t afford to buy it. I’m not losing my cookies over that fact and you shouldn’t either. Our bikes are coming.


I won’t know until I ride it whether that fork is a paradigm changer in handling. Same with the hydration unit, the down tube storage, and the aerobar comfort and ultimate adjustability. It all looks good to me, but the proof of the pudding is in the riding. Launches like this are like Match.com first dates: You know if (s)he’s not the one right away. Some new bikes fit into that category. Instant fail for some reason. This bike? I like it. I'm ready for the second date. But I haven’t hiked my leg over the top tube yet.

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