PezCycling News - What's Cool In Road Cycling : Fast Talk With Zipp Wheels

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Fast Talk With Zipp Wheels
Cadence Cycling, home of everything bling in cycling and known for service to match, holds a lecture series on the first Saturday of every month. The guys from ZIPP Speed Weaponry were featured recently, and presented some pretty interesting stuff on what they do to make wheels fast, and riders faster.

It’s all about the wheels… ZIPP Wheels.

Jim Douglas, Zipp’s International Sales Manager who I had the pleasure of meeting at Zipp’s factory during a quick visit to Speedway, Indianapolis, and Sandy Chapman, originally employee number “5” at Zipp, and now an independent sales rep for Tifosi Sales, Inc., paired up as two of the most knowledgeable sources for everything Zipp. There was a lot covered and some life saving things learned, well maybe just seconds, but first a few facts for Pez readers.

• 90% of Zipp Products are manufactured in Speedway. (A short walk from the home of the Brickyard 400 and Indianapolis 500 auto races)

• Zipp is up to about 130 employees with all Engineering and R/D in-house except for one person who telecommutes from Tennessee.

• Zipp has NEVER paid an athlete to use their products. NEVER. This was a mantra from founder Leigh Sargent.

The event attracted the usual Philly speed freaks – like local TT organizer Ashley Hawri.

The group of attendees was made up of local recreational riders, avid racers, and the father/daughter team of David and Ashley Harwi. David and Ashley organize the weekly informal time trial on Philadelphia’s West River Drive (Now MLK Drive) every Saturday Morning at 7am April-September. The Philadelphia time-trialing community owes a big thanks to them and last year both Cadence and local shop Breakaway Bikes teamed up to give David Harwi a brand new set up Zipp 404’s. His TT times immediately improved.

Note the snazzy wheel display rig.

How Fast Should I Go?
David Harwi, the expert at logging everyone’s times and calculating their TT speed, asked Jim “at what speed do the wheels really make a difference?”

Jim paused and said that Zipp had recently tested about 65 wheels for 13 hours per day over five days at the San Diego Low Speed Wind Tunnel. According to Jim “the gain is greater at 30mph but not to worry because the relationship is linear.” Jim went on to explain that the “benefit is consistent no matter what speed you’re at. “Sandy added that “the energy savings from aerodynamic wheels are also consistent.”

Remember when these wheels used to be fast?

Myth One: Deeper Isn’t Always Better
Zipp engineers are looking to build wheels that perform better under “normal” conditions, or what they call “the sweet spot.” Check Zipp’s white pages on for the jibbery stuff but basically wheels are designed for a wind angle of 0-20 degrees. It’s not realistic that a 90 degree wind would hit you for most, if any part of your ride. Factoring in conditions will determine how deep of a rim is optimal. Rim shape has also changed in recent years to show more of a “bulge” as opposed to “deeper” to find that sweet spot of aerodynamic efficiency. In short, Tour riders don’t ride discs up the mountains do they? According to Zipp you have to know where to draw the line.

Dave Berson admires a very aero wheel, while his son Henry admires a giant teether.

Myth Two: Bigger is Better
According to Jim Douglas it is “better to run a 23mm tire as opposed to a 19 on a Zipp 404 clincher.” (And a 21mm tire is optimal on ZIPP Tubular rims.) Jim went on to say that “there is a measurable, proven, aerodynamic advantage to having a bigger tire on your wheel.” Douglas describes it as “counter intuitive” but the break-track allows for wider tires, which creates better aerodynamics than previous wheels.

The rim shapes have been specifically designed to be fastest at these widths as these are the most realistic widths people use.

ZIPP’s research has also shown that 19mm tires have higher rolling resistance, wear out faster, are more likely to flat, and offer less cornering grip than a wider tire, so they design from scratch around a 21 or 23mm tire that the end customer is more likely to use, resulting in a better all around package.

You can refer to Zipp’s white pages for the details behind this.

Heard of Flash*Point Wheels? They’re Zipp, Just Less Expensive.
Raw Carbon is expensive and the build process is labor intensive. For only about $1,100 Zipp now offers their line of Flash*Point wheels that are 100% engineered and manufactured by Zipp, but priced below their standard wheels.

What’s the difference then? Zipp shaved some dollars by using a “weave” of carbon as opposed to “uni-directional” for their standard line of wheels. This cuts down on the cost of the raw materials and post-finishing time. The wheel design, hub, and performance are the same as all Zipp wheels, only the cost is less. According to Douglas “from quality, technology, and cost there is nothing out there like it.”

Tough Enough For Cobbles
Team CSC broke 9 sets of wheels at the Tour of Flanders in 2005 and they were very happy about that, because they'd broken 14 Ambrosio rims the year before. Josh Poertner, ZIPP’s r&d guru, confirmed that ”all of those breaks were simply rim cracks and were all discovered after the race with no riders needing wheel changes. In 2006 we only broke 2 rims, again, noticed after the race. So far this classics season through Ghent we have had zero rims break, which is unheard of. These numbers sound big, but remember that CSC has every rider on carbon wheels every day, where most teams maybe allow 1 or 2 guys on the wheels and even then not on any cobbled races. The only exception is Paris-Roubaix, where some riders have chosen them, but most go with those massive aluminum rims built onto Zipp hubs as they prefer the added lateral flexibility over the craig-head type cobbles.

Rolling resistance is also affected by the amount of glue used and how the tire was mounted. Make sure your mechanic is good. Poorly mounted tires will not only cost you time but will also wear faster.

Tubeless Zipp wheels are probably not going to happen. I didn’t say never but according to Douglas the shape of the bead line would change significantly which they believe does not provide a significant value or advantage to the road market.

Jim’s Recommendation?
Cadence coach Colin Sandberg asked what would be the best all-around wheel for the average rider for all conditions. Jim’s eyes lit up and said that for reliability, performance, and overall usage the 404 was his pick.

And I just got a new 404 Powertap SL for my birthday!

For more info check out:
• Information on Zipp’s Flash*Point wheels is available at


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