The Numbers Game
I get a lot of questions from readers about purchasing dilemmas, and I do my best to answer them all. The questions range from what saddle is best (I have a favorite, but unless your pelvis is a clone of mine, you might not like it), to clothing sizing issues (hard to do without being in the same room with samples in hand), to the typical frame selection and sizing questions.
The single most recurring question that I get from friends and readers is what wheel to choose. For someone purchasing a single set of high-zoot wheels, what would I recommend? And because I’ve reviewed more wheels from Zipp than Enve, Easton or other manufacturers, the question is often framed as, would I recommend the 202, 303 or 404?
It’s not a tough question for most riders, at least in my opinion.
For the purpose of this piece, I’m going to use Zipp wheels, but I think a number of wheels, such as those by Enve or HED, could be substituted for Zipp in this comparison. The point isn’t the brand, it’s the category. And frankly, getting a handle on the competing aerodynamic claims from one manufacturer to the next isn’t something I care to undertake—the marketing claims prove each brand is faster than their competition.
Before I get into the considerations that lead to the choices I would make, I want to lay out a few assumptions that guide my thinking. The first is that because I’m aware that a set of Zipp wheels are more expensive than some bikes, I don’t really see them as something I’d routinely take to a race, even if I was still racing. Sure, I’d use them in a time trial, and I might have been willing to use them in some road races, but the average crit isn’t a place I’d be willing to risk a $10,000 bike, unless, of course, I was sponsored to ride it—and even then I’d have a fair amount of trepidation. So while a great many people think you ought to save your most expensive equipment for race day, I think if you’ve got good stuff you ought to go ahead and ride it.
The second assumption is that fast is fun, and faster is more fun. So while I may be riding long training rides with a select group of friends or the occasional gran fondo, I want to ride as fast as I’m able. To that end, I want aerodynamic wheels for all the free speed I can get. Third, if I’m going to be on aero wheels, I don’t see any point in being frightened when riding in a crosswind; I want wheels that offer handling as close to that of a box rim as possible.
So now for a bit of objective data. The images that follow I got from Zipp. They offer a fairly objective comparison of several different wheels against the 202, 303 and 404.
For me, there a few takeaways from these images. The most striking is how a traditional box rim is aerodynamic equivalent of an elephant. The improvement of the 202 offer over a box rim is significant, but considered against the 404, I can’t help but wonder why a greater effort hasn’t been made to make a relatively lightweight aluminum rim that offers better aerodynamics (and handling) than the box rim. To my eye, the industry has given up. The best offerings I can see in the sub-$1500 range are HED’s Jet series wheels which mate an aluminum rim with a carbon-fiber fairing. What else is noticeable is how much more crosswinds affect the box rim and traditional V rims, and while I’ve seen how Firecrest (and other similarly rounded rims) handle better in the wind than V rims, it is interesting to see that phenomenon illustrated.
The basic wisdom on rim depth is that the flatter the course, the deeper the rim, and vice-versa. It’s the single easiest way to choose, but it leaves out all the nuance that causes lunatic cyclists like me to actually fret over these decisions. The discussion that follows isn’t about the obvious choices, it concerns the nuances that make you second guess.
The big knife
For riders across most of the world, where flat land dominates, the wheel that makes the most sense is the Zipp 404. That’s the simple truth. The weight penalty is more than overcome by the aerodynamic gains. Why deny yourself that aerodynamic advantage? Now, that said, there is a caveat to that selection. If you’re a light rider and you live in a place where the wind is a frequent training partner and if gusts are an issue, you may want to consider selecting a different front wheel, such as a 303 or 202.
There’s a lot of new technology that addresses the wind’s input on steering. Zipp’s Firecrest, Enve’s SES and HED’s Jet rim shapes have all used a rounded spoke bed that has fundamentally changed how the wind affects the wheel. Not only are the aerodynamics better, but the handling, as I’ve written previously, is much better than the previous generation of V rims. My first experience with Firecrest was on a pair of 808s and the on-shore breeze in the afternoons here can push me around as easily as a pro defensive lineman. The 808s were so easy to deal with in crosswinds I wondered if I was on Punk’d. It’s worth noting that Tom Boonen told me he starts every race, except for cobbled ones, with a 404 front and an 808 rear.
Where the 404 becomes an issue is on climbs. Its aero advantage disappears at speeds below 20 mph and then there’s the extra rotational mass of the deep rim to consider. But the issue the 404 faces is less going uphill than dealing with changes in terrain. When I’m on climbs that change grade the liability I encounter is in trying to accelerate the bike when the grade lessens. It’s not a huge issue, but the 404 flat-out doesn’t accelerate as easily as the 202. I think if I were riding in the Rocky Mountains consistently, where downhill speeds can easily eclipse 50 mph and the grades on climbs can often hover around 5 percent, I’d still go for the 404, but in the undulating grades of California’s coastal mountain ranges, there’s another wheel I prefer.
Mountain goat
The 202 Firecrest is a wheel I was excited about even while it was still on the drawing board. It features the same 16.25mm clincher bead width as the 404, giving the tire a bigger footprint for superior traction in corners (handy when descending), but at only 1343g for a set, as opposed to 1562g for the 404s. That’s not a huge difference in weight, but as all of the difference can be found at the rim; you notice it any time you start winding up the wheels. The combination of aerodynamics and low weight make it a climber’s dream, but only if your heart is set on clinchers.
The 202 does feel faster than a traditional box-rim wheel, but I can’t say that I sense the difference between it and the 303. However, on the flats and on descents, I hit higher speeds with the 404. I also notice a difference on descents between the 202 and the 404: The shallower 202 is more maneuverable in turns. By contrast, the 404 feels more stable and gives me confidence at speed.
I can’t stress enough how impressed I was with this wheel’s strength when I went down back in October. I went from 30 to zero in about the amount of time it takes to sneeze. The front wheel, which is what did the stopping, didn’t even come out of true. While Zipp wheels do flex some side-to-side, the incident did a lot to confirm for me how much stronger their rims are than they once were.
The wheel of all trades
And so what of that in-between depth of 40 to 50mm? If your home terrain has got a few sustained climbs of at least 5k, hills like politics has liars or roads bumpy as a bipolar’s emotional life, then the 303 may be your ideal choice. It’s a wheel that is light enough to climb well and yet still packs a powerful punch on the flats. It has gotten great play as a stout wheel for cyclocross and races involving pavé. Featuring the widest rim in the Zipp stable, the 303 yields the broadest tire footprint if any Zipp wheel, making it preferable for anyone concerned about tire adhesion in corners.
At 1478g, the 303 isn’t much lighter than the 404, but I’ve experienced them as being much easier to accelerate, or at least what passes for me accelerating. It makes them more cooperative on climbs while still lending a powerful aerodynamic edge on the flats and descents.
It’s worth noting that Enve has taken a slightly different approach to their SES-series wheels. Rather than using the same rim front and rear, Enve uses a shallower rim in the front. The 3.4 wheels use a 35mm-deep rim front and a 45mm-deep rim in the rear. Practically speaking, it’s like running a front 202 and rear 303. The 6.7 wheels use a 60mm-deep rim in the front and a 70mm-deep rim in the rear. The front is effectively a 404 while the rear splits the difference between a 404 and an 808.
If you’re only going to buy one set of Zipp wheels, chances are the 202 won’t be the best choice. I can only see buying the 202 if you live in a place that is binary—either up or down. I know there are people out there who think about purchasing high-zoot wheels for race day and saving them for special occasions. I’m not down with that thinking. Any day you put a great set of wheels on your bike is a special occasion. They, after all, are not like a bottle of wine which is destined to last but a single night. You don’t have to work very hard to take care of any of these wheels, so you can do consistent miles on them without fear that each ride is death by yet another paper cut.
I can’t claim that can always feel the improvement in aerodynamics of the 4o4 over the 303 or the 303 over the 202. On long, fast flats, my sense is that I’m just faster. I’m usually going too hard to reason my way through it at the time. But I seem to have a lot of good days with the 404s. What I can say for sure is that the 404 is noticeably faster than the 202; I’ve swapped the two out and been able to note the improved speed, even when the switch was one day to the next.
Coastal California isn’t like most of the rest of the world, though. The world is, for cycling purposes anyway, flat. Most places I’ve ever visited merit the 404. And that’s a handy thing. Whether you consider the 404, Enve’s SES 6.7, HED’s Stinger 5 or any of a host of other options, the real point is that once you have a chance to ride with your friends over known roads, you’ll be amazed at the advantage the wheels give you. Granted, some of these flat places experience a lot of wind. Even with the rounded profile of a rim like Firecrest, there can still be some steering input. For lighter riders who want some aero advantage with as little steering input as possible, I’d suggest a front 202 with a rear 404 or a set of wheels like the Enve 3.4.
There are a great many products that might increase your enjoyment on the bike, but very few I can swear will make you faster. For purely selfish reasons I should probably shut up so that the guys I ride with don’t all start buying aero wheels, but that would really violate the spirit of this site. We want you to have fun out there, and there’s no denying that more speed is more fun.















