THE BEST AERO BIKE WHEELS
Aero bike wheels look fast, ride fast, and race fast. At 55mm to 65mm deep, they are the racing bike wheels of choice for most road races including crits and can also work as triathlon wheels if you who want one set for multiple racing events.
For those who don’t race but want to go our fastest in training and on competitive group rides, especially on flat and rolling courses, the best aero bike wheels can give you that extra aerodynamic performance when it’s your turn to pull or sprint for the town line yet can still provide the stiffness, handling, and comfort you’ll find in all-around wheels 10-20mm shallower.
In this post, I review and compare some of the best aero bike wheels available today and say more about why riders and racers should consider them.
Related: Looking for all-around carbon wheels for your road disc bike? Click Best Carbon Disc Wheelset
Related: Not sure what kind of wheels to get? Click Road Bike Wheels – How To Choose The Best For You
WHAT YOU NEED TO KNOW ABOUT AERO BIKE WHEELS
Click on any red statement below to go directly to that part of the post
The ‘Best Performer’ ENVE SES 5.6 is a snappy wheelset that excels in nearly every measure
See the list of wheels I didn’t review and a brief explanation why
WHY YOU SHOULD CONSIDER AERO WHEELS
The world that most cyclists know is flat. Pancake flat for the most part and even flatter than an IHOP pancake in the case of a half-dozen US states according to researchers. Unless you live in or near the foothills of the Rockies, Sierra Nevada or the Appalachian Mountains, those of us who ride in the United States and Canada are going to be on pretty flat roads most of the time with no more than an occasional and short hill that exceeds a 5% grade.
And despite the wonders of the Alps and other mountain ranges featured in the summer pro stage races, Europe is mostly flat too. The European Plain, which runs from the Pyrenees along the Spanish and French border all the way to the Ural Mountains in Russia “gives Europe the lowest average elevation of any continent” according to no less an authority than the Encyclopedia Britannica.
Australia, New Zealand, and the South Pacific? Pretty much flat, flat and flat. The Sydney Morning Herald reported that “after more than four years” work, the final topographic maps, covering Australia, New Zealand and more than 1000 Pacific, Indian, and Atlantic Ocean islands” developed from radar data taken by the space shuttle showed that “Australia was the flattest continent in the world.”
As for the mountains, I’m told by some well-placed elves that only 12% of the world’s population actually live there.
So why do so many of us look to buy (and read my post recommending) climbing wheels? Perhaps it’s because many of the most famous cyclists going back to icons Eddy Merckx and Fausto Coppi to the modern-day heroes like Nairo Quintana and Chris Froome conquered the cycling world climbing mountains.
And why do we focus so much on wheelset weight when choosing between one or another? Perhaps because weight is one of the most quantifiable differences between wheels, even though for most riders, reducing our own body weight by 2.5kg or 5lbs would save us 5x the amount of time we would save cutting 300-400 grams by replacing our stock wheels with a good set of climbing ones.
If you are a serious regular cyclist or what I call a road cycling enthusiast (see here for definition), you need to focus on aerodynamics and aero bike wheels, two things that are critical to cycling fast on the mostly flat earth we ride.
Weight only matters when you are accelerating and when you are going up steep hills and climbs beyond 7% or 8%. But, as explained above, the weight that matters most is your body weight and how much power you can crank out relative to your weight. Your bike and wheelset weight have little relative effect when accelerating and climbing until you are super fit, well trained, and looking for incremental gains.
Unlike weight, your aerodynamics almost always matters except when you are drafting off of someone in front of you or slowly going up steep grades. And the faster you go, the more it matters. Aerodynamics even matters more than weight when you are accelerating, though the difference between the effects of the two is marginal in that situation.
If you regularly average about 19mph or 30kph and faster on your rides, aerodynamics matters a lot and can save you minutes based on how you position yourself on your bike and what gear (wheels, frame, tires) and kit (helmet, jersey, etc.) you use.
If you are averaging anywhere near 25mph or 40kph on your road rides and races, you are leaving a lot of money on the table – or perhaps drag on the road – if you aren’t locked into what better aerodynamics can be doing to save you time and power.
The chart below summarizes this; the posts on training and technique (here) and gear and kit (here) go into more detail on how to go faster including the role of aerodynamics.
So if you want to go faster, an aero wheelset is part of what will make it happen.
But aren’t aero wheels just for time trialists and triathletes, those poor fools that bend over with their hands out in aero bars for miles at a time, not having to worry about making any sharp turns, with no other riders near them to maneuver around, and going so ridiculously fast that those freakishly deep rims they ride on really make a difference?
Yes, aero wheels are certainly for those riders and they will be on very deep rims, often more than 60mm deep and as much as 90mm deep or complete discs in the back wheel. But aero bike wheels, those in the 55mm to 65mm range are also road racing bike wheels and regular riding wheels for fast roadies riding on flat and rolling terrain.
In 2010 Zipp introduced the 404 Firecrest carbon clincher, a product that changed the direction of high-performance wheelsets. The Firecrest rim had a rounded “nose” where the spokes attached to the rim and toroid-shaped rim sides rather than the pointy nose, V-shaped profile that deeper rims had at that time. It was also several millimeters wider at the brake track than most other wheels and was 58mm deep.
Testing showed the Firecrest had less aerodynamic drag than wheels much deeper and weren’t buffeted by side winds the way even shallower wheels were. As a bonus, you could actually slow these carbon-rimmed wheels down without growing old waiting for it to happen and losing your hearing from all the screeching coming from the braking action.
The Firecrest wheels set a new standard for rim and wheel design.
Most of the leading wheelset companies followed with carbon clincher wheels that emulated the Firecrest 404 shape and depth. Many also introduced triathlon wheels in the 70mm+ range to compete with the Zipp 808 Firecrest for the speed-demon, TT and tri riders. Another group of shallower, 30-45mm deep carbon clinchers also came out for “all-around” riding and climbing led by the Zipp Firecrest 303 and later the 202.
In the last several years, more and more 55-65mm deep, carbon-clincher wheelsets with “blunt” noses and either toroid or U-shaped rims with 17mm, 19mm, and even 21mm internal widths and 26mm to 30mm external widths have been introduced for both rim brake or road disc bikes. Tests show these aero bike wheels are nearly as fast as the very deepest triathlon wheels.
The best of these don’t get pushed around by crosswinds, are stiff and comfortable, handle well, and are faster yet as responsive and indistinguishably light as the many carbon all-arounds that are 10mm to 20mm shallower. They compare well or better against many of the same performance criteria that I find matter when choosing wheels (see here).
Below, I share with you the conclusions I and my fellow evaluators reached after riding many of the best aero bike wheels that you can use as racing bike wheels or for riding fast without needing to race. I’ll also tell you which wheels we didn’t consider and why.
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ENVE SES 5.6 – A snappy wheelset that excels in nearly every measure
ENVE introduced the SES 5.6 in 2018 as the successor to the SES 4.5. When I last reviewed this category of aero bike wheels, I picked the 4.5 as the best performer. After comparing the wheels in the category this time, the SES 5.6 is the one I’d choose to ride on.
No, I don’t have an ENVE tattoo anywhere on my body. And sadly, I returned this wheelset just like every other that is sent to us to demo for reviews.
In fact, among all the wheelsets I rode this past season, I enjoyed riding the ENVE SES 5.6 more than any other one. While my riding profile would normally suit a shallower wheelset, I’d happily ride this one most any day of the week.
The SES 5.6 is more responsive than any other wheelset I’ve ridden including shallower and lighter ones. It jumped forward when I wanted to move out or ramp up my speed while underway. When I cranked up the watts going up rollers, up steeper hills or working to close a gap, it was stiff. And it handled precisely and confidently going fast downhill and into corners
This ENVE wheelset seemed to take less effort to go fast and held my speed incredibly well. I didn’t measure watts vs. mph but it sure felt like I was putting out less of the former and getting more of the later than any other wheelset I can remember. You know when you feel like you are going fast but not working that hard? You look down at your speed and say to yourself… whoa, I’m going fast. It felt like that a lot on these wheels.
The Chris King hubs on the SES 5.6 rolled very smoothly. They were comfortable on tubeless rims with their 20mm inner width. I also felt confident braking on the textured rim brake tracks that emitted a slightly higher frequency and lower volume than the Zipp’s textured brake track.
On a fall day full of crosswind, the ENVE SES 5.6 compared favorably against the Bontrager XXX 6 and Zipp 404 NSW that I rode back to back to back. And the Bonty and Zipp were amongst the best I’ve ridden in crosswinds in this racing bike wheels category.
So that’s my take. For context, I’m a B-group, 18-20mph enthusiast on an endurance frame. I don’t race or time trial but I do try to ride fast.
Nate is my evil twin tester. While we weigh practically the same (150-155lbs – that’s the twin part), he’s an A-group ride leader, does road races, hill climb events, and even the occasional TT. He wins some of them in a pretty tough age group. And he has a stiff S-Works Tarmac racing frame.
He’s also a very, very nice guy but truly evil if you try to outdo him on the road.
Nate and I reached similar conclusions about the SES 5.6 on some criteria and different ones on others. He really liked how they performed at high speed and how well they maintained their momentum once there. “Wheeeee!!!” was the technical term he used to sum up his aero evaluation.
He also liked how they accelerated from a stop or when he wanted to make a big power burst while already at speed. They were noticeably tougher to climb with than the 40mm-50mm carbon wheels he normally rides, but he found this to be true of many of the wheels in this racing bike wheels category. That was my experience too.
For the record, the wheelset we rode had Chris King R45 hubs and came in at 1559 grams on my scale, the same as what ENVE claims for them. The front wheel was 5g lighter and the back 5g heavier than what ENVE claimed but obviously, well within the margin of error and manufacturing tolerance.
If you think riding a 1481 gram wheelset will help you climb better, you can save those 78 grams (and get a quieter freehub too) by going with the ENVE carbon shell hub on these wheels for the same $3000 price as the one we rode with the King. Alternatively, if you prefer spending $2550 for the wheelset, you can spec it with the ENVE alloy shell hub at 1593 grams.
Nate didn’t love the SES 5.6’s ride and handling. At least, he didn’t love it compared to the equally stiff Bontrager Aeolus XXX 6 or the more forgiving Zipp 404 NSW.
Using the Goldilocks testing method on all three wheelsets, he found ENVE wheelset rode too hard at 80 psi, was less accurate at 65 psi, but at 72 psi offered the best combination of comfort and handling. (FYI, I rode it at 60 psi, closer to where ENVE suggests riders that weigh what Nate and I should).
While Nate found the ENVE and Bonty equally responsive at 72 psi, to him the ENVE seemed to exaggerate the roughness of the road at that pressure while the Bontrager and Zipp wheels dampened it.
In the crosswinds, Nate felt ENVE and Bonty were better than the Zipp.
Nate summarized his evaluation of the SES 5.6 using the practical framework of ride time and road terrain.
“Over shorter rides (<3 hours) without too much elevation or on smoother roads, I’d take them in a heartbeat…there are some KOMs I’ve been needing to claim back and these might just be the right tool :-). However for longer rides and certainly on my stiffer bike frame, I think I’d rather have the smoother Zipp/Bonti ride, even if sacrificing some of ENVE’s responsive snap.”
So bro, I guess we come out at much the same place?
I would summarize it this way: The ENVE will make an already comfortable endurance bike ride stiffer and more responsive while the Bontrager will make a stiff bike ride more comfortably.
ENVE also makes a road disc brake version of the SES 5.6 that use rims claimed to be 85g lighter than the rim brake model. Overall they are claimed to be about 50g lighter than the rim brake model for the $2550 version with the ENVE alloy hubs.
You can click on these links to top-ranked stores Competitive Cyclist and Merlin Cycles or this link to Know’s Shop to find and order the ENVE SES 5.6 rim and disc brake wheelsets at the best prices from the best stores.
WHEELSET COMPARISON CHART
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Bontrager Aeolus XXX 6 – High-performance aero cruiser lacking responsiveness
Getting great stiffness and comfort in one wheelset is a tough combination to pull off. When you do, you can deliver many additional performance benefits as by-products. Bontrager’s Aeolus XXX 6 makes this happen unlike any other set of aero bike wheels we’ve reviewed.
The first thing you notice about the Aeolus XXX 6 is just how comfortable it feels. It rolls beautifully and sucks up rough roads and imperfections so well it seems like you are riding on a far better surface than the one your eyes tell your brain you are.
Nate called it “amazing” and commented that he could feel the difference in comfort within a couple of hundred yards of leaving his house.
Don, a member of our gear testing team who does Ironmans and half triathlons, also noted how much better the XXX 6 was at absorbing rough road conditions than other wheels he’s ridden.
At 21mm internal width, this and all the Bontrager Aeolus XXX models are some of the widest of any of the rim brake wheels intended primarily for paved roads. But don’t jump to performance conclusions based on its specs.
The ENVE 5.6 at 20mm internal rim width and also run tubeless on the same tires and at the same pressures during our test rides didn’t provide the same level of comfort. Only the Zipp 404 NSW at 19mm and run tubeless matches the comfort of the XXX 6 among these aero bike wheels.
But, hey, if you are a racer or speedy roadie, comfort is nice but it’s not why you ride. You want to go fast. And while a comfortable wheelset may make it seem that you aren’t going as fast as you are, on these Bontrager wheels, you are also going fast.
Let me say that again. You are going fast when you ride these Bontragers.
The stiffness of this wheelset certainly helps create speed. Riding the XXX 6, it feels like there is no slack between your pedals and the road. Your power transfers directly. The handling is also precise, making you faster in corners. It all feels very tight, like a good horn section in a well-practiced band. (Tower of Power anyone?)
An independently run and ongoing aero drag test done by Hambini Performance Engineering has to date compared nearly 40 wheelsets of different depths from a range of brands. One of its key findings is that wheelsets of the same depth essentially have the same aero performance. The Bontrager Aeolus XXX 6 and XXX 4 wheelsets, however, have shown to be a notable exception that perhaps proves the rule that this finding suggests. Their aero performance was on par with wheelsets 20mm deeper.
There’s been a fair amount of push back from some wheel designers and cycling industry leaders about Hambini’s testing protocol. It uses the transient drag methodology adopted by the aerospace industry rather than the static one employed by most in the cycling industry.
From my humble understanding of cycling aerodynamics and my experience riding a lot of wheelsets, I saw some things that I really liked about the testing – its independence, seemingly more real-world conditions, and the sheer number of models it compares.
There were also some things about it that didn’t seem to sit well. The test used the same width tire regardless of the rim width. This seemed at odds with all I’d learned about the aero benefits of keeping the mounted and inflated tire no wider than 95% of the rim so the air coming off the tire would stick to the rim rather than separate from it. Was it possible that a wheelset with a wider rim like the XXX 6 performed better than one with a narrower one (as most were) because the tire width allowed the air to stick to the Aeolus longer?
Regardless, refer back to what I wrote above. You go fast when you ride these Bontragers.
Hambini also concluded that wheels of the same depth all felt the same amount of crosswind force regardless of their profile. Anecdotally, I’ve never found that force to be felt the same way even if it is the same amount. Wheel designers creating new deep rim profiles have done a lot of work over the years to reduce the effect of crosswinds by moving from box- and V-shaped rims to “toroid” or 0-shaped and U-shaped rim profiles with rounded and “blunt” noses.
On different windy days, Nate and I ran back to back crosswind testing of the Bontrager Aeolus XXX 6, ENVE SES 5.6, and Zipp SES 4.5 NSW. I found the Bontrager managed those crosswinds noticeably worse than the other two wheelsets. Nate found the Bontrager on par with the ENVE with the Zipp lagging. Not conclusive.
One thing Nate, Don, and I did agree on was Bontrager’s superior braking abilities. Because the wheelset is stiff, you can position the pads closer to the rims on these aero bike wheels than on others. That gives you better modulation right off the bat.
Second, the braking is quieter than those like the ENVE and Zipp which have aggressively textured tracks. And third, there isn’t much drop off in the Aeolus’ braking performance between dry and wet roads the way there often is on other carbon rim wheels that smooth brake tracks as the Aeolus does.
On the downside, the three of us also agreed that the Aeolus XXX 6’s acceleration and climbing left a lot to be desired. They were a far ways off the snappy ENVE SES 5.6 and underperformed three of the other wheelsets we tested in this category.
As aero bike wheels that are often used as racing bike wheels, was this weakness less important than some of the Aeolus’ strengths?
Don, our triathlon cyclist called them “sluggish” on hills and noted there aren’t many tris he rides that are flat enough that he wouldn’t notice this. Nate, our road racer and climber extraordinaire said they “weren’t great” going uphill.
I wrote the word “lethargic” down in my log after riding them for a couple of weeks. They were great once I got them going but my B-group power took a while for that to happen. I couldn’t get them to accelerate like others I’d been riding and I really struggled on them going up 5% grades.
Maybe I was fatigued or had been riding too much before I started testing the XXX 6? When I did the back to back to back crosswind testing, however, I confirmed the lethargy I felt from the Bontragers compared to the highly responsive ENVEs and Zipp 404 NSW whose responsiveness I rated average against all the wheels I tested in this category. Seeing Don’s and Nate’s notes was further confirmation.
The weight of these Bontragers, which I measured at 1669 grams with the tubeless rim strips installed, is 110 grams heavier than the ENVE and nearly 50 grams heavier than the Zipp both also taped up for tubeless tires. That amount isn’t enough to explain the different acceleration and climbing different we felt.
Note that Bontrager claims the XXX 6 weight at 1530g, 140g lighter than I measured it. Bontrager uses plastic rim strips to set the Aeolus wheels up tubeless and they do add this much weight. If you prefer to run them with a tube and tire, you can remove the rim strip and use regular tape.
The Aeolus XXX 6 is a speedy, stiff, comfortable cruiser which handles and brakes as well as any in this category of racing bike wheels. It’s likely best suited for riding and triathlon racing on flatter terrain rather than road racing and crits that requires quick accelerations or riding rolling or hillier terrain.
If those strengths match your riding or racing profile, you can buy a set up the Aeolus XXX 6 wheelset direct using this link to Trek. Bontrager also makes a disc brake version of this wheelset using the same rims that has a claimed weight 45g heavier than the rim brake model evaluated here.
Mavic Comete Pro Carbon SL UST – Comfortable speed but slow to get there
The most versatile aero bike wheels perform well both as fast, responsive accelerators for the quick speed changes and maneuvering needed in road racing and as the flat-out speed demons in steady triathlon and time trial riding.
If you don’t race but still ride fast, the best of this category of aero bike wheels work just as well for aggressive group riding on rolling courses as they do in fast training rides on flat terrain.
The Mavic Comete Pro Carbon SL UST wheelset is a very fast wheelset that maintains your momentum wonderfully when you are rolling at 20mph/32kph and faster. For steady rides on flat terrain, it is a smooth, high-speed cruiser. Combined with its ample compliance, the Comete give you comfortable excitement at speed that tracks confidently in a turn.
On windy days, the Comete definitely gets pushed around by crosswinds though I experienced more of a predictable sine wave sway than a hard, sudden spike. While I’d prefer less (or no) crosswind effect, I can manage this type of crosswind effect better than an uneven, unpredictable one.
While the Comete is also a stiff wheelset, it doesn’t feel nearly responsive enough to accelerate with most of the racing bike wheels in this category. Quick changes in speed and direction aren’t the Comete’s forte. It is also a lot more work getting up even 3-4% rollers.
The Comete’s weight may explain some of this. I rode the disc brake version which measured 1798 grams on my scale vs a 1755g claimed weight. If the rim brake model weighs the same 45g or so above the claimed weight, it would likely weight about 1680g. That would put it about 120g above the ENVE SES 5.6, the snappiest of those in this racing bike wheels category.
Mavic’s rear hub, similar to the DT Swiss design in its use of dual ratchets rather than pawls, has a distinct Mavic freehub sound. It’s the same freehub internals used in the ENVE 5.6 wheelset with ENVE’s new branded alloy freehub, louder than the DT Swiss used in the internals of the Bontrager, on par in volume though different in character than the Chris King hub used in the ENVE 5.6 we tested, and, of course, louder than the silent freehub used in Zipp’s 454 NSW.
Mavic has a lot of fans of the brand and all the reliability that comes with it. If you are one of those fans and are looking for a flat terrain, speed cruiser, the Comete is certainly worth considering. You can click on this link to top-ranked store Competitive Cyclist or this link to Know’s Shop to find and order the Comete rim and disc brake wheelsets at the best prices from the best stores.
Zipp 404 NSW – Fast and comfortable but stiffness disadvantages it against the best
The original Zipp 808 and 404 Firecrest wheels helped define the aero bike wheels category. The 404 Firecrest were among the first carbon racing bike wheels used in professional road races. Many pro and amateur racers also used the nearly 60mm deep 404 as a front wheel paired up with the 82mm deep 808 as a rear for time trials and triathlons. As more road riders took to triathlons, they used the 404 Firecrest wheelset for that event in addition to doing road races, group rides, and training.
Yes, the 404 Firecrest wheels were expensive but you only had to buy one wheelset to be fast across a range of riding profiles.
At just the time that carbon wheels, clinchers, aerodynamics, triathlons, and road racing became more popular, Zipp had set a performance bar. Zipp expanded the Firecrest line to the shallower 303 and 202 based on the same rim profiles and other design and ride characteristics that had made the 404 Firecrest so successful.
Other wheelset companies took note of what Zipp and HED, who shared the original patent for the toroid-shaped rim profile that led to fast wheels and applied it exclusively to tubular models, had done. Carbon clinchers with wider, rounder shapes became a very competitive market with established and new players competing with the design and aero performance levels that Zipp and HED started.
While Zipp went through a succession of different hub designs to make the Firecrest wheels more durable and improve their stiffness, the NSW was the brand’s first new rim design and replaced the Firecrest as Zipp’s new top-of-the-line wheelsets in 2017. This was roughly 8 years after the 404 and 808 Firecrest went into production.
Zipp introduced a second generation NSW in 2018 and made the 2017 NSW rim the heart of its new Firecrest line, selling it for about $1000 less than the NSW.
While only a year apart, Zipp made major changes to the rim used in the 2018 404 NSW. While the same depth, the shape changed, its internal width increased 2mm to 19mm, it became part of Zipp’s first tubeless family of wheelsets and was offered in both rim and disc brake versions. The hubs that were entirely new for the 2017 NSW were retained for 2018s.
So a lot has changed in a short time. The brand name is the same but there is little about the performance of the 404 Firecrest that you might know or have heard about that applies to the performance of the 2018 Zipp 404 NSW wheelset
How do they perform?
The Zipp 404 NSW are fast wheels. Whether it’s the rim profile and width or the smooth rolling and quiet freehubs, both the sensation and reality is that these wheels roll fast underneath you.
While not quite as snappy as the ENVE 5.6, the 404 NSW are very responsive wheels that others in this category don’t match. That responsiveness extends to the handling as well. When you want to change direction, the 404 NSW does that very quickly.
They are very compliant rolling over the mix of surfaces you might find on a long ride. Not that you should, but you won’t feel the urge to alter your line or brace yourself for short rough patches you see in the road ahead. Instead, the ride is comfortable, pleasant, joyful, and fast.
The 404 NSWs aren’t as stiff as some of the others in this category and this takes away from some of the benefits of the wheelset as a whole. Responsiveness without stiffness gives you the ability to move out quickly but not the power efficiency to do something about it. And while you can get in and out of turns quickly, a lack of stiffness brings down the precision or riding-on-rails feeling once in the turn.
As Nate noted in his test rides, these Zipp wheels probably have the best absolute braking power of those we tested in this category. Don added that the brakes were clearly the loudest. I had a similar reaction on both counts in my test rides though wasn’t bothered by the brake noise.
Despite the 404 NSW’s superior braking force, its inferior stiffness requires you to set the brake pads wider than you need to with the several stiffer wheels in this aero bike wheels category. Otherwise, the rims will rub against the pads as the wheels flex when you get out of the saddle or sprint. With the brake pads opened wider, you diminish the modulation or your ability to feather the brakes to vary the amount of brake force you want to use.
The net result of all this? The NSW’s brakes are less than they could be and don’t match the performance level of the ENVE SES or Bontrager Aeolus wheelsets.
Nate and I were also disappointed with the Zipp 404 NSW’s performance in the crosswind where its shallower 303 NSW sibling performs so admirably. Here again, while not bad and better than some (see the comparative charts), it required more correction than the ENVE 5.6 in separate head to head testing we did with several of these wheelsets on windy days.
Knowing the 404 heritage, I probably hold the bar quite high for this newest 404 NSW model. And it performs very well or holds its own against many of the criteria we feel are most important. But others have now passed it several key areas.
If the 404 NSW’s strengths align well with what you are looking for in a set of racing bike wheels, you can click on this link to top-ranked store Competitive Cyclist or this link to Know’s Shop to find and order the rim and disc brake models at the best prices from the best stores.
Vision Metron 55 – A good bargain for riding mostly flat terrain
The Vision Metron 55 might be better off changing its name to keep its 55m rim dimension a bit of a mystery. That’s because it rides differently than the stereotype its depth would suggest. It is a very stiff wheelset and holds its speed like a deeper one would. At the same time, it handles, manages the crosswinds predictably, and accelerates like a shallower set of wheels. Braking is on par with the majority of carbon wheelsets with untreated brake tracks regardless of their depth – fine when the sun shines, a bad bet when it’s wet.
Another irony is the Metron 55’s acceleration, which is pretty good, vs. its weight which not so good. Acceleration can overcome weight with a stiff and responsive wheelset, which this one is. And while I’ve cautioned you, dear fellow enthusiast, not to put much stock in a few grams difference here or there when comparing wheelsets, the rim brake Metron 55’s actual measured weight from three sources I trust comes in at an average of 1705 grams (+/- 20 grams).
This is consistent with my own experience with Metron wheels measuring about 100 grams more than their claimed weight. Note that the disc brake model adds another 110 grams in claimed weight over that of the rim brake Metron 55.
While many wheel makers seem to have scales that somehow calibrate 50 to 100g less than those of riders and reviewers, getting above 1700 grams puts you up in the same class – on a weight standard – with less versatile aero bike wheels that are good for flat riding and triathlons but not for road racing. While most 55-65mm deep wheels are not those you want to climb tall mountains with, you’ll notice 150 grams of difference between wheelsets including these Metrons powering up short, 5% rollers that any all-arounder should cruise up without wondering what they are dragging.
The only other comment I’ll add is that three other reviewers I trust wrote that these same hand-built Metrons came to them out of true. While I’ve not experienced this issue with the Metrons I’ve tested, and it’s certainly one that can be easily fixed, you need to be vigilant when inspecting this wheelset after you first receive it.
Vision wheels are frequently discounted from the prices recommended by the company. You can click on this link to top-ranked store Competitive Cyclist or this link to Know’s Shop to find and order the Metron 55 rim and disc brake wheelsets at the best prices from the best stores.
If you ride more flats than rollers, want an all-carbon aero wheelset that’s plenty stiff, and can keep wheels true or have someone who can, the Metron 55 at the right price is worth considering.
Easton EC90 Aero 55 – Stiff and fast but loud braking and poor in the crosswinds
When Easton first introduced the Aero 55 in 2014, the company’s marketing material proclaimed the it “the most aerodynamic road wheelset on the market today” and “fastest in all conditions.” It was quite bold and who knows if it was true, but at least they had the balls to publish their testing protocol and results for wind tunnel tests comparing their Aero 55 tubular and clincher wheels against the Zipp 404 Firecrest, HED Stinger 5 and ENVE 6.7 tubular models.
Zipp, HED, ENVE, and many others have since introduced new aero bike wheels but I’ve seen very few comparative tests published by wheelset companies or industry pubs. The Aero 55 wasn’t included in Bike Radar’s lab test or the independent one conducted by Hambini Performance Engineering. Easton now claims “World Leading Aerodynamics” on the web page for these wheels.
Easton also shared results of their tests using different model and size tires on these wheels. Both the wheel and tire test results are published on page 3 of their white paper here. The tire test results are below.
What I find most interesting in their data is not necessarily who has the fastest wheels. Rather, the Easton tests show that the time differences between the wheels are about the same as the time differences you get by changing tires. This shows that you can mess up the speed you are trying to gain spending $2000+ on a set of wheels by picking the wrong $150 set of tires, usually by going too wide.
Note that of the ones they test, the 21C, 22C, and 23C tires are the fastest in that order, and they don’t test 25C clincher tires nor do I assume they recommend one if going fast is a priority. Get your comfort from the extra volume in the rims, not the tires, unless speed is less important than comfort, in which case you probably are looking in the wrong aisle for your next wheelset. (I’m talking to you Mr. “I must put a 25C or 28C tire on whatever wheel I ride because that’s what everyone else says I should be doing”.)
I bought a pair of Zipp Tangente 23C clincher tires to run on these wheels. According to the chart, the 21C size of the same model would be a lot faster but I wasn’t sure if I’d ever use a 21C again after evaluating these wheels so budget considerations got the better of me this time. (See, I do it too!) Once mounted and inflated, the 23Cs measured 24.7mm wide on these 19C rims. That’s still over 3mm narrower than the 28.1mm rim width I measured at the brake track. So I was doing my small part to improve the aero performance.
In hindsight, I expect even a 25C size Schwalbe Pro One or Continental Grand Prix 4000S II (the new 5000), models which typically measure around 2mm wider than the size rating once installed and inflated, would have been slightly narrower than the brake track width once installed and inflated. But I found the wheels comfortable enough with the 23C tires on to go for the aero benefit.
While the EC90 Aero 55 was first rolled out years ago, many of its design attributes are still considered modern. Easton had one of the first, if not the first carbon tubeless clincher wheelsets available in a 50mm+ depth and one of the first to go ultra-wide with 19mm bead and 28mm brake track widths. Reynold’s Strike went tubeless in 2015, HED’s carbon-alloy Jet 6 Plus came out as wide as the Aero 55 in 2014 and Bontrager’s Aeolus 5 D3 followed in 2015.
So does the Aero 55 hold up against the competition 5 years removed from its introduction? I rode these wheels for a few hundred miles and then asked Nate, one of the fastest roadies in my cycling club who also does crits and TTs (without aero bars) to give them a go solo, in group rides and in a weekly TT near him.
We both found them very stiff and responsive to changes in speed while underway. That stiffness also helped Nate, who weighs the same but is far younger, stronger and faster than me to get good acceleration from a rolling stop. I had more difficulty getting them up and going than the ENVE SES 4.5 I was testing around the same that weighed just a few grams less than the Aero 55 which read out at 1591g on my scale.
The Aero 55 holds its speed well, is comfortably compliant and handles confidently for an aero wheel with 23C tires. It also rides quietly, with only a little of that slicing or swooshing through the wind sound that you can get on some deeper carbon wheels when riding them really hard. Nothing that seemed to affect or take away from the riding experience. The hubs were also quiet while freewheeling, a characteristic I prefer vs the click-click-click you hear from other hub models.
Nate was impressed with the braking force whether the rims were seeing their first braking action in a while or after repeated braking in a relatively short period of time. Braking under damp conditions required more distance but nothing out of the ordinary for carbon rims with untreated brake tracks.
In dry conditions, the brakes start squealing when you brake them hard, long or repeatedly. The SwissStop Yellow brake pads that come with these wheels also leave a pollen colored ring on the rim. Yes, it comes off if you wash your bike regularly but it’s really bugly (look it up) while you are riding. I’d think Easton could quiet the rims and avoid the coloring with a better choice of pads. You’d be better off with the SwissStop Black Prince.
Both Nate and I agreed that these wheels didn’t handle the crosswinds very well. We’re lightweights and got pushed around a good deal, far more than I’d experienced with other deep racing bike wheels. On a day with a fair amount of crosswinds, Nate didn’t feel stable on the Aero 55 in his normal aero position during a TT and bailed for a more open one.
With a new generation of aero bike wheels arriving from many different quarters and many enthusiasts getting on board with road disc bikes, perhaps Easton has left this model unchanged for too long. If the braking noise and crosswind performance aren’t issues for you, it’s sold for heavy discounts when you can find it.
Easton has recently introduced an Aero 55 disc brake model with the same rim profile that should eliminate the braking issue on a wheelset that otherwise has some good things going for it. You can find the rim and disc brake models at the best prices from stores I recommend at this prefiltered link to Know’s Shop.
Roval CLX 64 – A twitchy ride reminiscent of days gone by
My mother used to tell me, if you can’t say something nice about someone, don’t say anything at all.
When it comes to the Roval CLX 64, I will say a few nice things about these aero bike wheels. If I took my mom’s advice, I’d probably leave it at that given my overall take on this wheelset. However, since I’m doing a review here and I always try to call it as I see it, I will say more. Out of respect for the wheelset designers, I’ll keep it short.
This CLX 64 looks appealing if you sort through specs to figure out which racing bike wheels to initially consider. It is one of the widest (nearly 21mm internal and 30mm external), deepest (64mm), and lightest (1596g rim brake and 1580g disc brake measured weights) in this category. It has a blunt nose, DT Swiss hub internals and a low number of bladed DT Swiss Aerolite spokes with external nipples.
At first blush, all of this suggests good performance.
Unfortunately, it doesn’t deliver on what the performance the specs would suggest. The CLX 64 rims bend easily and this negatively affects the wheelset’s acceleration. The underperforming stiffness may also contribute to its poor handling, something you really have to adjust for taking corners at speed by making sure you balance your weight as best you can on the front and back wheels.
Despite the CLX 64’s excellent overall braking power, you have to keep the calipers open far wider than normal to prevent the wheels from hitting the pads on typical accelerations, let alone getting out of the saddle or sprinting. Having the pads relatively far from the rims also gives you the antithesis of modulation; it seems like all or nothing when it comes to slowing down.
These deep Rovals also get blown around pretty easily, even on days with just light winds. In fact, shifting your weight a bit to reach for your water bottle or something in one of your pockets can induce instability that borders on a wobble.
But wide, tubeless rims leads to a comfortable ride, right? Who knows. Setting these wheels up tubeless is a big league hassle. The tire beads don’t seat particularly well in the rim hooks even with a compressor and the tires lose air far too quickly once the sealant is injected and tire is fully inflated.
The term “twitchy” should have left the cycling lexicon when we went to wider tires on wider, carbon rims with rounded, wind-cheating profiles. Despite its design, this Roval CLX 64 wheelset’s challenges with stiffness, handling, crosswind management, braking, and tire sealing provide an experience that seems like a throwback to an earlier era of bike racing wheels.
WHEELSETS NOT REVIEWED HERE AND WHY
Full Priced Carbon
Campagnolo Bora WTO 60 – Announced in 2018, it has been slow to become available for enthusiasts especially with a Shimano freehub (link to Know’s Shop). I’ve not been able to get a hold of one yet to test. If I do, I’ll add it to this review.
DT Swiss ARC 1100 Dicut 62 and Swiss Side Hadron 625 – These are the same wheels with different cosmetics, branding, and marketing stories. The rims are designed by Swiss Side and manufactured by DT Swiss and use DT’s 240 hubs and Aerolite spokes. The wheels are relatively narrow (17mm internal, 23mm external at the brake track) and are heavily discounted from their original asking price though still just under $2000 (link to Know’s Shop for the DT Swiss ARC 1100 wheelset).
We can’t review ’em all and it looks like this one is due for a serious update to be competitive from a design and demand standpoint. I’ll wait for the successor model.
ENVE SES 4.5 – I evaluated and chose this wheelset as the best performer in my first review of aero bike wheels several years ago. It was my first love in this category and instilled the faith in me that a wheelset this deep could be versatile enough for riding a variety of terrain at used in a range of road racing events. ENVE came out with SES 5.6 as the successor of the 4.5 and, as I’ve written above, I recommend it as the new Best Performer in this category.
According to the customer service rep I spoke with at ENVE, the 4.5 will stay in the company’s line-up, principally for those riders with bikes which don’t have the clearance for the 5.6’s wider rims. If that’s you, here are the links to top-ranked stores Competitive Cyclist and Merlin Cycles and to Know’s Shop to compare prices and order the SES 4.5.
Fulcrum Speed 55 C – For this 55mm deep clincher wheelset and its Speed 40 C sibling, Fulcrum took the earlier tubular versions of the same design and converted them to clinchers. Yes, they added a brake track treatment that makes them perform better and more predictably and they have the awesome Campy CULT hubs. However, the V nose, 17mm internal/24mm external rim that isn’t tubeless ready makes it a derivative design.
Stiff but not comfortable (and not tubeless ready), fast but pushed around by the crosswinds (even the 40 C), it’s ready for an upgrade. You can get it for about $1750 (link to Know’s Shop) but there are others of similar design vintage like the Vision Metron 55 reviewed above that you can get for less and performs better.
HED Vanquish 6 – Chalk this up in the column of haven’t but hope to ride it soon. HED famously refused to go down the development path of carbon clincher rim brake wheelsets, concerned that the heat generated in braking rendered such wheels unsafe. The Vanquish 6 is a disc brake only all-carbon wheelset. I’m currently testing the Vanquish 4 and hope to ride the Vanquish 6 soon. If you can’t wait, you are in good company and can follow this link to top-ranked store Competitive Cyclist or to Know’s Shop to buy it online at stores I recommend.
Reynolds Aero 65 – This is another wheelset I would like to review but haven’t had an opportunity to do so as yet. You can read my review here of the Aero 46 disc brake wheelset that has similar design characteristics to the Aero 65. The 65 isn’t widely available online but you can find it through this link to top-ranked store Competitive Cyclist for about $2000.
Shimano Dura Ace C60 – The rim brake C60 is a relabeled carbon alloy C50 wheelset. I say more below about why I haven’t included carbon alloy wheelsets in this review. The disc brake C60 doesn’t seem terribly modern in design and isn’t widely available. Yes, I’d like to review it at some point but it isn’t high on my priority list.
Zipp 454 NSW – Nate, Moose and I evaluated this wheelset for our last comparative review of aero bike wheels. You can find our take on it here. I’ve left it out of this review as it didn’t compare well on a performance (or price) basis. Except for its novel varying rim height, the 454 NSW rim is based on the original 2017 404 NSW, one that has been significantly updated in shape and width and now runs tubeless on the second generation 2018 404 NSW reviewed above. The 454 NSW has yet to be updated and still has an internal width of 17mm and requires tubed or tubular tires.
Many brands sell 55mm and deeper wheelsets in the $1000-$1500 range. I’ve been digging into the broader group of wheelsets I call “value carbon” in a multi-part examination and set of reviews starting with my post The Best Carbon Wheelset for the Money – Part 1.
While that post focuses on 40mm – 50mm all around value carbon wheelsets, many of the same companies also sell deeper wheels at similar prices. I believe much of what I’ve found in my research for that review extends to those selling aero bike wheels.
It’s a broad generalization but from what I’m finding so far, the saying that you get what you pay for appears to hold true among value carbon wheels. The question we roadies each have to ask ourselves is whether we need all that the full-priced wheels provide.
There are 10,000 words about this in the post I linked you to above so I’ll stop here and encourage you to go there if you are interested in reading more.
The late Steve Hed and his HED Cycling company were one of the original innovators along with Zipp in aero wheel design. They demonstrating that a wide rim, round-nose, toroid-shaped rim could give you lower drag and better crosswind management than a traditional narrow, flat-sided, V-shaped one.
Unlike Zipp however, he didn’t think that carbon clinchers could manage the heat energy produced during braking. Instead, he focussed his innovation on deep carbon tubular wheels and also developed carbon-alloy wheels using the toroid rim shape. This second group of wheels combines a shallow alloy inner structural rim to dissipate the braking heat bonded to an outer carbon fairing to get the desired drag performance. You get the aero benefit of the deeper carbon rim shape with the superior braking of an alloy wheel.
Other companies – most notably Shimano, Mavic, and Campagnolo – who are more conservative in their product design initially followed the same braking philosophy as HED and made carbon-alloy clincher aero wheels instead of all-carbon ones. While these wheels were sold for far less than all-carbon clinchers, they were also far heavier and best for riding flat terrain and doing triathlon and time trial events.
While HED and Shimano still sell carbon alloy rim brake wheels, Mavic and Campagnolo now make all-carbon rim brake wheels. HED and Shimano have also begun making all-carbon disc brake clincher wheels. None of these companies has introduced a newly designed carbon-alloy wheelset in some time.
The introduction of the class of value carbon wheels has given options to those who want the lighter weight of all-carbon aero bike wheels at the lower price of carbon-alloy ones.
For all these reasons, I don’t think there’ll be much of a market for carbon-alloy wheels going forward and suggest you look for a better option among the all-carbon aero bike wheels available.
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