Zipp’s marketing manager Andy Paskins took a working vacation from Zipp’s frigid Indiana headquarters, to ride in the sun, eat Mexican food and share with Road Bike Action, the latest improvements that the most prolific carbon fiber wheel builder imparted upon its deep-profile 808 and 404 wheelsets.
Andy proved to be in better shape than we expected from a mid-winter Midwestern Racer. Cyclocross, it seems, is his secret.
Zipp’s 808 tubular wheels, we learned, were once thought to be relegated to time trialists, but their aerodynamic slipperiness and lateral stiffness has won over mainstream pros and the 81-millimeter section, molded unidirectional carbon rims are now regularly raced in ProTour road events. Previously, the 58-millimeter profile 404 was considered to be a radical choice for road racing due to the fears of the pro peloton that cross-winds would play havoc on deep-section aero wheels.
Zipp 404 wheels on the wickedly fast BH G4. 13.5 pounds and ready for a solo breakaway. Would 808s be faster still?
The aero profile of the 808 is not as simple as it appears. There are actually five engineered curves in the profile that, in conjunction with Zipp’s patented dimpled surface, coax air over and around the tire from angles up to 25 degrees without amassing significant drag numbers, The key function of the aero wheel is to encourage the wind to wrap closely around the wheel without creating lift or turbulence. Lift acts to toss the hapless rider off the road when gusts attack from the side, and turbulence exaggerates the negative effects of wind drag. Zipp doesn’t pretend—they test and retest each component in the wind tunnel until they are assured of positive results. Andy says that compared with the first-issue 808 wheels, the new 808s will save nine seconds over 40 kilometers at the same watt output. If you use a PowerTap, that is a 2 to 7 watt reduction at 30 miles an hour. Zipp sells the 808 wheels in tubular or clincher configurations.
Before you question the benefit of a mere nine seconds over 40 K, consider that the total savings over that same distance when compared to a conventional aluminum racing wheel is 81 seconds (27 watts), an you might get the same wakeup call that Zipp's ProTour racers are responding to.
What could you do with 81 seconds mid-way through a race? That's almost certain victory for time trialists, but don’t discount the benefits that aerodynamic wheels bring to the road racer. Fabian Cancellara races 808s in road stages—his quote: “The 808 is the new 404 to me.” Imagine getting to the climb over a minute early. You could climb a little slower and not get gapped at the top. Bridging gaps and sticking solo breaks would be slightly easier—and as Cancellara proved, 808s may be the secret to a successful one-kilometer finish line attack. “Slightly” is most often the difference between victory and defeat in the road racing game-but 1.3 minutes? Well, even if Zipp's data was 50-percent in error, it would still make the 808s a must-have.
808 UPGRADES:
A stiffer carbon layup for the rim adds a few grams to the 808, but improvements in the hubs (higher flanges and a stronger straight-pull spoke interface) allowed Zipp to remove some spokes without compromising its now-legendary lateral stiffness. The new 808 uses 20 bladed Sapim spokes in the rear and 16 for the front wheel. The higher flange of the rear hub’s drive-side is paired with radial lacing to increase spoke tension and boost lateral strength. The left side of the wheel is laced two-cross. The weight? How does 672 grams (front) and 790 grams (rear) sound? Clincher wheels are slightly heavier. Zipp’s $2485 retail price is the same for tubular or clincher models.
The 808’s hub is all new. Note that the drive-side flange is radial-laced and the non-drive-side is cross-laced ala Mavic Ksyrium.
SPEAKING OF CLINCHERS:
Where most carbon clincher rims use an aluminum rim with a carbon fairing, the Clincher versions of the 404 and 808 wheels are designed as a working whole. The aluminum rim and molded carbon are bonded using a mechanical interlock and the spoke interface is on the carbon section—a tiny detail that eliminates three inches of stainless steel spokes that other wheels must carry around. The advantage of the aluminum insert for the otherwise carbon rim is that aluminum makes a better braking surface and it dissipates heat. Carbon clincher rims can (and occasionally do) fail when heat buildup compromises the epoxy carbon matrix and boosts tire pressures to above-maximum levels.
Zipp’s 404 clincher illustrates their bonded-in aluminum rim, and the 58-millimeter aero profile. All of Zipp’s spoked wheels use external nipples now, so that mechanics can true them more easily.
HUB ROUND TABLE
Andy was pretty excited about Zipp’s redesigned 88 and 188 hubs. They are slightly heavier than the previous models, but offer significantly better sealing as well as a stronger spoke interface. The freehub design uses four pawls with individual return springs, so a broken pawl will not compromise the remaining three and end a race. Both front and rear hubs use tubular, 17-millimeter aluminum axles for stiffness without a weight penalty, and they roll on Swiss-made sealed ball bearings. Zipp inserts a red-anodized dust seal between the bearing and the outside world to protect against invasive chemicals and overzealous pressure washing. Using a 2-millimeter Allen key, the hub retaining nut can be adjusted to perfectly tune the bearings’s side play. The nuts themselves are aerodynamically profiles and designed to be angled correctly into the airstream when the wheel is inserted into the frame and fork. Hub weights are in their names: 88 grams (front) and 188 grams (rear)—and they are made at Zipp’s facility in Indiana.
Zipp’s 188 rear hub exposed. The entire hub can be disassembled by hand with a single Allen key. The serrated freewheel ratchet (pressed into the aluminum hub flange) is carved from heat-treated stainless steel with an EDM machine which disintegrates its way through the super-strong metal with an electrically charged wire.
AND, THE RIDE?
Andy installed Zipp 808 tubular wheels on two of our lunch-ride race machines. The 808’s tires were Zipp’s Tangente models made by Vittoria. The dimpled tread pattern of Tangente tires further enhances the aerodynamics of their wheels. It was a Zipp wheel day–one of us was riding 58-millimeter section 404 wheels and another member of the RBA peloton was using Zipp’s should-be-illegal 202 climbing wheels. We were in luck that day, because the hour-long sprint was being assailed at every angle by sustained 25-mile-an-hour winds. Without a serious cross-wind component, we would not have been able to test Zipp’s claim that through careful aerodynamic profiling, the deep-section 808 rim would not react violently to gusty side winds.
The ride proved educational. The 808s were manageable in the howling winds, and best of all, lacked the noisy rumble that many deep section wheels have. Zipp’s unrelenting quest to remove every unused gram from the wheels creates a truly aerodynamic wheel that is lightweight to the degree that its sprinting and climbing performance is unaffected. That, in itself is an advantage, because the 808 rider can dish out punishment at 33-miles per hour on extended flat sections of the course, without giving it back on the climbs. The 808 riders did wave around a bit in the pace line when passing trucks broke the airstream, but by rides end, the group was reacting to crosswinds about equally. The deep-section riders admitted that it was easy to stay on line as long as the crosswinds were steady, but they were working harder when it was gusty, or if the wind was momentarily blocked. The verdict was that most of the wind-induced wiggling was due to over-controlling by the rider after the bike was blown slightly off course. It was RBA’s consensus that learning to be comfortable on the 808s in all conditions should only take about a month.
And what about the 404 rider? No big deal, in fact, Cancellara may be right. Anyone who spends a lot of time in the front of the peloton, or solo into the wind, should consider using Zipp 404 wheels to take advantage of the reduced drag. The 404s are no brainers—the 808s….well, think of them as an unfair advantage that, in the hands of a skilled road racer, could inflict serious damage to his or her competitors.
For more info and a look at Zipp’s entire lineup, CLICK HERE
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