Review: Reynolds 58 Aero Wheelset

The consumer market on aerodynamic, all-carbon road racing wheels has been, to say the least, flimsy.

It's been dominated by wheelsets made for one task only – going fast – and companies such as Zipp and Mavic have created "time trial" and "tri" wheels for years. But as a consumer, you had to make a choice: Do I want all-carbon 90 mm wheels that'll make all the other gearheads drool? Or do I want wheels that are reliable and capable of taking on the terrain that a rigorous ride requires?

If you're looking to reduce weight, go fast, and win races, perhaps the single best upgrade you can make to your road bike is to pick up a good set of aerodynamic carbon wheels.As technology becomes more advanced, materials become cheaper, and minds grow brighter, there's more innovation happening in the area of competitive racing wheels. In other words, now we can have both – a drool-worthy, all-carbon wheelset that can reliably handle any just about any road condition.

Reynolds is at the center of that breakthrough with its [new Aero line](http://www.reynoldscycling.com/index.php? p_resource=items_wheels_item&p_itm_pk=660). It's been adapted from the company's RZR line of wheels we all know and love, but could never afford. When I got word about the new advancements in airflow technology being used at Reynolds, I jumped at the opportunity to test the brand new Aeros. The results were eye-opening to myself and the other bike nerds here at Wired, and they satisfied all the rumors we'd heard through the grapevine. Foremost, that these wheels defy the very laws of physics. Impossible, you say? OK, yeah, sure, whatever. Thanks for the note, science guy.

The lab at Reynolds has put an exorbitant amount of time into researching and testing a proprietary airflow technology called Dispersive Effect Termination (DET). It premiered three years ago in the RZR line and has trickled down to the 2013 debut of the Aero line, which comes in 58, 72 and 90-mm profiles (clincher only) and at a lower price point than the RZR ($2,775 for the 58mm).

The shape is reminiscent of a teardrop, which makes visual sense, but apparently has a history of failure among manufacturers.

"The DET contour is the closest contour to an airfoil that you'll find in the cycling marketplace," says Reynolds' director of technology and research Paul Lew, who has significant experience in these areas – he used to make low-drag airfoils for UAVs for the U.S. Government. Lew also designed the carbon fiber hood on the Corvette ZR1.

All the rims for the Aero line terminate at the spokeface with a sharp trailing edge – the defining feature of the DET technology, and a shape no one else is really taking advantage of. Lew describes why this rim shape is unique: "If you review Simon Smart's [Enve] patent, he acknowledges that an airfoil contour is more efficient than the Enve contour (more round). However, he points out that molding a tapered trailing edge in carbon composite is very difficult, and probably not feasible."

Another goal for manufacturers is the development of a tapered shape that can still integrate securely with the nipple area of the spoke without creating turbulence and allowing a seamless and attractive transition.

"Reynolds has a heritage of molding carbon composite," Lew says, "and as expert practitioners, we have experience that transcends bicycle wheels. This experience and aptitude for molding benefits us by removing limits as to what we can manufacture when it comes to difficult contours."

Basically, Lew's team has been able to stretch the limits and create the most aerodynamic wheel shapes possible. Wind tunnel tests show the new shape minimizes the ballooning effect of the turbulent air around the rim, reducing the yaw seen in other designs. (The Aero line was tested against the Enve 6, Zipp 404 and 808, Easton EC 90 and HED 6 and 9). The unique shape also shifts the center of pressure forward of the hub, which greatly improves handling while riding.

This was proven over and over again while testing these wheels. The Headlands served as my proving grounds – an area where us Wired folk (and just about every other bay area bike enthusiast) often ride after
work. It's riddled with hills and a gnarly crosswind that only gets worse the more turns you take. Comparing the Aero against Mavic's full-carbon wheelset is polarizing. There were rides where I literally lost control of my bike while on the Mavic wheels – something you don't want to do on any road, let alone one with a shoulder that drops hundreds of feet into the Pacific. On similarly blustery days, I was always in command of the Aeros, and was delighted to find the crosswinds felt drastically diminished. Ride after ride, in Marin, at Ocean Beach, climbing Hwy 1, the Reynolds wheels never failed to cut through winds that were constantly battling against me. The significance of how well they performed in harsh winds can't be understated.

Another feature is something Lew describes as a "step-hook," which is visible on the outermost contour of the trackpad. It's a small concave groove that takes advantage of the clincher hook's shape to reduce drag.

"This step creates low pressure," Lew says, "and as the air passes over it, this low pressure encourages the fast-moving air to follow the contour of the rim better."

The rims on all sizes are 26.2 mm wide, accomplishing two things: answering the call for wider, sturdier rims, and smoothing air flow in transition from the front of the tire to the face of the rim.

The other important advancement on this wheelset is the safety and reliability of the braking system. Even considering that time-trialists don't need to hit the brakes all that much, why has it taken so long for wheel manufacturers to make a full carbon rim that you can actually stop? Again, while testing the Mavic Cosmic Carbone Ultimate last year during our annual Wired Bike Test there was overwhelming disappointment in the braking system's performance during quick stops and on hilly descents. The pads screeched at 100 decibels and barely accomplished the minimum requirement of stopping the bike. It's another example of how more recent developments have failed to make full carbon wheelsets sensible to the consumer market. Reynold's CTg (Cryo Blue technology), developed two years ago, is changing that.

Lew was once a professional triathlete and understands the importance of a good brake system.

"The Reynolds CTg system was developed to do two things," he says. "One: Stop. Two: Stop with minimal heat generation." Smart thinkin', Paul.

The second part of that statement is key – companies have struggled to make a braking system that doesn't result in a massive amount of thermal gain, which in many cases can reduce strength in the carbon's epoxy. Having your wheels crack or warp from overheating is undesirable, yes – but so is not being able to stop when you need to. Traditional pads made from materials like cork and rubber just don't cut it anymore. Lew developed a proprietary polymer-based brake pad that marries well with the carbon epoxy and doesn't heat up too badly when you put the squeeze on. This magical pad pairs the maximum fiction coefficient with the lowest possible temperature increase.

I had much more confidence when I was testing these brakes than I've felt with the others I've used. Heading back toward the Nike Missile site on the same ride I mentioned before is Marin County's most grueling (and beautiful) descent. One lane, and dropping nearly 800 feet over 2.5 miles of cliffside road peppered with hairpin turns. It's a descent where you really don't want to mess up. Thankfully, the Cryo Blue system responded better than expected. Two of my test rides involved moderate rain, and even then the stopping power was more than adequate on descents.

There are some additional advantages to this wheelset, starting with a stylish profile. A few of the fashion trends in the bike world are giving me a headache lately, but Reynolds has chosen an understated and stylish look that gives your bike a "serious business" vibe. The flat spokes are much smaller than current market trends, allowing the performance to do all the talking. They weigh in at just 1580 grams per set – slightly heavier than some of the top competitors' similarly sized rims, but the pricepoint makes these a better bargain. The Aero line comes stocked with DTSwiss 240S Straightpull hubs with a smooth and quiet 11-speed rotor, also new for 2013. Your 10-speed Shimano or Sram-compatible rear cassette will also slide right on there with no adjustments necessary.

If you're looking to reduce weight, go fast, and win races, perhaps the single best upgrade you can make to your road bike is to pick up a good set of aerodynamic carbon wheels. This is true especially now that the latest advancements are being integrated into new products that sell for a lower cost. It's not necessary to sacrifice performance for stability anymore (or visa versa). The Aero wheelset doesn't sit atop Reynolds' product line, but in my opinion, it might as well. Lew and his team have designed it as if it does. All the luxury of a premium wheel is here, and frankly, other full-carbon aero wheels have mostly failed in comparison to these in road tests. Reading about advancements is one thing, but experiencing them firsthand is another entirely.

WIRED Wider, sturdier rims at a slimmer price point. Aerodynamic airfoil shape that defies the wind. A proprietary braking system that actually works.

TIRED Heavier than some of the competition, so weight weenies will whine.