It was a highly-detailed info request by Zipp staff last month as they prepared a test bike for industry editors for a press event in Tucson, Arizona this week. “Please include frame stack and reach, tip of saddle to back of pad, overall drop from top of saddle to top of pad and saddle height.â€ Certainly more detailed than the standard “send us your frame sizeâ€ request.
“Wow, seems they really want to ensure the fit is dialed in,â€ I thought. Interesting.
When I arrived to Tucson and learned that Zipp’s product debut was for an integrated aerobar. I nearly rolled my eyes. Integrated? “Cool, but why bother with all those fit metrics if they were gonna stick editors on a fixed-position, no-adjust integrated bar?â€ I wondered. As I would learn, it was an introduction into the new world of bike fit: the unification of aerobar into the stack and reach construct.
And yes, that integrated aerobar—the new Vuka Stealth—would have nearly as much adjustability as a standard bolt-on stem would provide.
“We really want to drive awareness that it’s great to save 15 grams of drag on an aerobar, but your body is 70 to 80 percent of the aero equation on a bike,â€ said Vuka Stealth lead designer Ben Waite. “For some reason, some people have been ignoring that for a while. Getting the frame fit right is great, but the aerobar is a contact point, and fitting that is just as important.â€
Monday and Tuesday, Zipp debuted several items in Tucson. One such product the introduction of the 650c 404 Firecrest carbon clincher which we discovered Mirinda Carfrae prototype testing at the Hawaii Ironman. Weighing just 670g for a front wheel and 795 for a rear with a rim depth of 58mm, and a true this full toroidal design with a 26.53mm max width carbon clincher, this one is going to be a godsend to smaller triathletes—see Rinny as Exhibit A. It’ll be 10- and 11-speed compatible, have SRAM/Shimano or Campagnolo freehub body options, and will hit the market in March and will retail for $1,227 for the front wheel, and $1,498 for the rear.
Zipp also debuted the 30 Clincher, a 30mm-deep hybrid toroidal aluminum-rimmed wheel (with a vertical braking surface, hence the “hybridâ€ denotation) that serves as great new cost-effective training wheel option. It also has a new proprietary hubset that is factory set with no pre-load adjustment. It’s $390 front/$460 rear, 10- and 11-speed compatible for both SRAM/Shimano or Campagnolo, and will be available in March as a nice little-brother option to Zipp’s 101 wheelset.
Aaaand… Zipp debuted an alloy-rimmed, Zipp 60, a 60mm. With a 58mm-deep profile and a dimpled hybrid-toroidal profile. It too will be 10- and 11-speed ready for SRAM/Shimano or Campy, and while not a super light climbing wheel at 850 grams front and 930g rear, it’s going to be a great all-arounder; an easily serviceable wheel (with external nipples) with training and race day dual capability.
Back to Zipp’s new unidirectional carbon fiber integrated aerobar. For years, these do-it-all bars were the hot ticket; they melded the stem and bar into a singular, aero construct that frontally was a cleaner leading edge presentation. But while most had a few length options (approximated to what a standard stem length would be), and minimal pad placement options, most had none; you either passed on the bar, or you wangled your body and position on the bike to make it fit to the bar—even if it didn’t. And that’s ill-advised backwards math.
Zipp’s solution was a long time coming: the Vuka Stealth. At first glance, it looks like many other integrated aerobars, with that melded stem/bar construct. The basebar itself is a UCI-legal 3:1 aspect ratio, with a Kamm-esque truncated trailing edge that makes for a bar as aerodynamically faster than it’s predecessor, the 4:1 Vuka Aero, which is not only much less adjustable, but also heavier.
Zipp said it’s not a true Kamm due to the swept design, however. It also features a front-and-center mounted (and removable) Garmin Edge twist-on bracket mount, and everything is secured by Torx T25 bolts. Zipp bar and post engineer Nathan Schnickel estimates that 70 percent of the bolts on the bar are titanium, with only the extension-fixing bolts for stacked setups being steel (given the propensity for incongruous torque loads).
But it’s upon more detailed inspection that the devil arises.
The first detail comes with size: it’s available in three options, indicative of the bar’s reach from the steerer: small, medium and large. But instead of drawing a parallel to a stem length (bar width will remain unchanged between sizes at 42cm measured outside-to-outside) based on steerer-to-pad measurements, Zipp is now building the sizing around stack and reach measurements.
Nailing fit will be easy. Not only does the bar come in three lengths, there is further length adjustment vis-a-vis a stacking shim; using a longer bolt will allow for 10mm of added length horizontally-loaded steerer clamp block.
Regarding vertical pad and extension stack from the basebar, the Vuka Stealth kit comes with riser options similar to that of the Vuka Alumina: 10mm, 25mm and 50mm towers. It also has the same spacious armrests and same adjustability as the Vuka Alumina (a bar that received rave reviews for its adjustability range).
The armrest’s fore/aft can be straddled forward or rearward of the extension clamp. Armrest faceting has width option from a nearly next-to-each-other 140mm to a spacious 276mm apart. “And if you’re like me and need it even wider, you can put on our wing extension kit; you get out to a little over 300 millimeters,â€ Schnickel said. “Quite literally, the inside of your wrists when holding the brake at the lever, are rubbing the outside of the pads.â€
The extension fixing clamps can also be situated outboard (for wide extension mounting) at 144mm wide or reversed to mount the extensions inboard for a more extension placement at 104mm wide. Of course, extension canting angle is fully adjustable as well. Shift cables can port either directly in-line into the extension or from slots at the base of the extension.
Consumers can purchase extension options separately (that is, extensions are not included with the bar) including Zipp’s Race, Straight, Ski-tip or Vuka-Shift styles. Further, any other standard 22.2mm-diameter extension from any other brand will work as well. “We’ve found that when we included extensions, they’re always the wrong ones,â€ Schnickel said. “We’re looking at it as a modular thing: you get the extensions that fit you the best, whether it’s ours or some else’s.â€
All told, the bar can uptake about every fit permutation, with zero fit compromises. In fact, Waite said there are 1,920 different specific adjustment positions the bar is capable of, considering potential morphological offsets, etc.
“What we feel we’ve achieved is an integrated aerobar that’s relatively light at 820 grams with extensions, but is very very adjustable,â€ Schnickel said. “It’s no longer a case of saying ‘I really want that cool integrated bar, but I gotta figure out the bike that will make it work for me’. Now you’re looking at a bar that’s super adjustable and can be fitted specifically to you.”
Certainly, making the mental adjustment to fitting based on stack and reach measurements may be easier for the tri market already familiar with the concept. However, it will require a bit of mental gymnastics for the road market. To that end, Zipp will be releasing a Vuka Fit app this spring that will do the math for you on which length bar to buy after inputting your stack, reach and pad width measurements. It will be accessible bout as a downloadable iOS app as well as a functioning app at zipp.com. Further, shops will be educated on the Vuka Fit protocol.
“You’ll put in your coordinates of fit stack to the top of the pad and fit reach to the back of the pad,â€ Schnickel said. “You’ll also put in your headset cap and length of spacers you have under your stem currently, and frame stack and reach dimensions. The app will then output a metric like “medium bar with stem block, armrests in X position in this facet. You get the entire setup of the bar, right away.â€
The product was a five-year work-in-progress under the work of Waite, and received its feedback and ultimate confirmation under the test of Zipp athlete Jordan Rapp as he quietly tested the prototype at the Hawaii Ironman last year. Truth be told, it’s amazing it took this long for a brand to incorporate stack and reach in this manner; to this point, the increasingly popular metric (measuring the vertical height and horizontal length of a bike) been a greater utility for frame size selection than traditional frame sizing has, particularly in the tri bike market with its unconventional designs. But aerobars were somewhat of an afterthought by many brands, with a name like Profile Design doing the best job. Last year, Zipp added its name to that short list with the Alumina.
Indeed, dialing your aerobar fit as a component of your bike fit is paramount as getting the right size bike. “Road riders have a lot more flexibility, because they have three positions; tops, hoods and drops,â€ Waite says. “But for triathlon it’s lock and load, you’ll be in one position—the aerobars—all day. The best position isn’t the one that creates the least amount of drag, it’s the one you can sustain and stay in.â€
Adds triathlon marketing director Dave Ripley: “If your fit is off and you can’t hold that position for the duration of the race, all that high-dollar aero gear advantage is just given back—thrown away.â€
So with three bar sizes, how much fit range is there? Zipp says the bars will fit 80 percent of all athletes save for outliers. (and that the brands own Vuka Alumina alloy bar/stem options would fit those outliers). However, the variability within the Vuka Stealth is going to hit the lion’s share of us, even within each size. “When you consider that Jordan (Rapp), who’s 6’1, rides on a medium bar, and that Rebecca rides a medium bar, on a 650c bike.,â€ Schnickel said. “That shows the variability within that one size.â€
Indeed, there will be outliers that may not fit a small or a large at the ends of the sizing spectrum, but Schnickel said they will be few. “We’re not gonna get all of ’em but we’re gonna fit a lot of the outliers. With the Vuka Alumina, then you get all the outliers.â€
The rest of the details reside in functionality; the bar’s internals have clean inner profile with minimized internal flash for low weight. That also means it’s easy to run brake and shift cable within. (We tested with a piece of housing and were able to fish it through without much trouble). On the back end of the basebar, a small, threaded nylon eyelet exists, allowing athletes to have cable housing run along the basebar’s trailing edge, keeping it out of the wind.
Further, the bar’s underside has not only ports on either side of the basebar for brake and derailleur porting, it also has a central port for the front brake for those either running now bar setups on small bikes, or those running center-pull style brakes, where such a setup would make for a cleaner, straighter cable pull.
Cost: $1,070, without extensions. Add a set of Race VukaShift extensions at $300 on their own, it’ll bump up a complete kit to $1,200
Well, the best rides are the ones you don’t notice. And it’s always alarming to notice a bar setup that doesn’t fit. We had no such alarms.
For all the email detail Zipp requested of the editors in order to set up the test bikes (in my instance, a Specialized Shiv Tri), it was the first time I’ve been set up and not had to move a thing on the aerobars before setting out for our ride—not one. On a bike with an integrated bar, no less. That’s certainly testament not to the mechanic’s ability, but rather to the Vuka Stealth’s capability.
I tested a medium Vuka Stealth on our ride from base at Starr Pass over Gates Pass, through three loops of rolling McCain Loop and back to base camp. All my contact points—forearms on the pads, extension length, extension canting, extension pitch, and pad placement in relation to my upper body, were set up perfectly; it was like easing into the aerobars of my bike at home—a Trek Speed Concept—that served as my fit baseline for metrics sent to Zipp a month ago.
I didn’t feel I was reaching too far to the shifter at the extension, or that the pads were too far ahead on my forearms, or that the pads were too far back and touching my knee when climbing out of saddle, or too wide or narrow. The steering axis was perfect. Again, the less you notice on a maiden voyage, the better the bar is. The only thing (for a hilly ride over Gates Pass on Tucson’s west side) the bar could have used was a bit of bar tape. Granted, Craig Alexander runs his bars sans tape for Kona, relying on the light grit built into the paint overlay of the bar. If we’re splitting hairs, that’s the only thing the bar could have used for our slightly hillier test.
As for other sensations, there’s that one signature that anyone who’s ridden a one-piece bar can enjoy: a remarkable lateral stiffness. Indeed, it’s not a big deal for folks that live on in flatter It makes for a bike that feels more “connected” as a complete construct. Climbing out of saddle (and going over Gates, there was definitely some climbing), it’s a remarkable level of stiffness that no other Zipp bar has ever provided. This may not be a big “advantage” to folks living in flatland Iowa riding straight on no hills for miles, but in sprint races when you’re out of the saddle out of corners, punching over small rises, or wrestling up larger ones, this is a nice feature.
And I can imagine that improved and added cable routing options on the Vuka Stealth will be an improvement over current options, especially with smaller riders where tight cable housing angles make things more challenging.
Once returning to Starr Pass, we had to consider who would purchase this bar, considering the amount of bikes like the Specialized Shiv and the Trek Speed Concept with their own integrated aerobar, meant exclusively for their machines. In reality, however, those super-integrated bikes are more of an exception than a rule; most bikes out at the races still run an aerobar off standard 1 1/8 steerer.
“A lot of companies are slowly pulling back from that kind of design,â€ Schnickel said. “Specialized initially had the Shiv TT with it’s own bar, and now it has the Shiv Tri that uses a standard 1 1/8. Same with Felt; they now offer their bikes with their bayonet front end, or a standard inch and an eighth steerer. Blue has done the same with their top tri bike. There are more opportunities for an integrated bar of this type.â€