We have all seen that person on the local group ride with wheels so deep we wanted to remind them this wasn’t a triathlon. The thing is, that wheel has the potential to be super-fast, but when is it too deep and what are the real benefits?
When Zipp reached out and said they have two new road wheels to show us, we were a bit surprised to see 80mm deep 808s and undulating 82mm-85mm deep 858 NSW wheels. We would usually leave those depths for TT bikes and triathlon bikes. Zipp assured us that there was no mistake and that their new 80mm+ wheels not only offered road riders aero benefits but also hit the scales at a weight generally seen on 40-50mm wheels.
Zipp is under the umbrella of SRAM which has some extensive resources when it comes to product development. A few years back Zipp started working with mobile aero sensors, allowing them to refine their computer optimization to the next level, with real-world results. Compiling all the data has led Zipp to develop rim profiles and rim geometry that are optimized for total system results.
What that means is they are optimizing the wheels for what actually makes you faster and not what has traditionally been thought to make you faster. The first is that the new 808 Firecrest is disc brake specific. This has allowed Zipp to refine not only the geometry of the rim but the composite layup and weight distribution. The new 808s have a claimed weight of 1635 grams, and our test wheels with tubeless tape and valves hit the scales at 1663 grams. For comparison, the previous 808 Firecrest MY22 was 1917g. That’s 282 grams lighter than the previous version.
Next, the wheels are tubeless and hookless, with 28mm tires being the optimized size. The internal width of the rim is 23mm, and the external width is 27.5mm. Since the rim is hookless the transition between tire and rim is almost flush, and Zipp claims it reduces drag significantly. While Zipp wouldn’t give us any specific drag figures, they did say that 9.6-11 grams of drag is equal to about 1 watt. The new 80mm deep rim shape is about 1 watt more aerodynamically efficient than the previous 808.
Zipp said that much of the performance gain in real-world applications is around rolling resistance. From their testing tire pressure that is low is much faster than tire pressure that is high. They do have an optimized pressure, but 1-2 psi over it offers a dramatic performance loss and 10psi under is only a few watts slower. They also pointed out that using their Tyrewiz pressure sensors, they found that pressures on “normal” rides fluctuate so much that you are almost always better off starting a few psi low, so you don’t surpass the optimized pressure which results in significant performance loss.
For their testing, they used an 85kg (187lbs) system (rider and bike) with 28mm tires and 68-70psi needs 5 watts less than their previous 808 on 25mm tires. The incredible part is that from 40-65psi you still get a 4-watt advantage but over 72psi brings you back to zero advantage and in a few cases actually results in more resistance. The moral of the story is that Zipp says setting the pressure at 40psi will give you a faster system than if you get it at 75psi. These numbers are assuming you match their 85kg system, but because of the larger air volume, the difference between a heavy rider and a light rider is normally less than ten psi.
Beyond the drag that happens externally from the wind, Zipp uses their ZR1 DB hub that is engineered in Germany to reduce drag but maximize performance. It offers a better seal design for improved durability over the life of the wheel and quicker response with 66 points of engagement using six pawls and 33 teeth. This is about a 5.5-degree engagement because only three of the pawls are engaged at a time, reducing what would normally be a 10.9-degree engagement in half.
As we have come to expect, Zipp seems to have the internal rim profile dialed for tubeless setup. We were able to install and dismount tubeless tires without any tools. We were also able to inflate the tire and seat it with just a regular floor pump. No mess or hassle, both tires were mounted in under 10 minutes and never needed to exceed 60 psi. For us, this is always an important aspect of modern wheels, and the new 808 passed with flying colors.
On the first ride, it was evident that these 80mm deep wheels completely changed the feeling and riding characteristics of our bike. We tested them on multiple bikes from lightweight bikes to aero-optimized bikes with aero tubes, and all had the same result. The way the 808s move the air across the rim and over the spokes is much different than what we get from a 40-50mm rim.
When riding at speeds of about 12-15mph we noticed an added level of stability, and at 18+ mph even a hefty crosswind was easy to manage. The only time we found the 80mm deep wheels to be overwhelming was in a canyon that had wind gusts, and we were between 7-15mph. The on-and-off pressure that was inconsistent made for a very eventful ride. We did however notice that in those same conditions if we could maintain speeds over 15-16mph the gusts had much less effect on steering.
The weight distribution is unique in the fact that spoke nipples are much closer to the hub as well as the reinforced section of the rim profile that the nipples reside on. This means that the weight has less radius when compared to shallow wheels or even the typical 40-50mm wheel. Since dynamic weight is largely affected by radius, these feel more like a 1300-1400 gram set of wheels to accelerate up to speed, maybe even easier.
In the past, the weight distribution was always a drawback to very deep wheels because there was so much reinforcement near the outer edge of the rim to compensate for rim brakes and very high tire pressures. With both of those factors now out of the equation, almost all of the weight savings are near the outer edge meaning less energy is needed to change speed. That goes for acceleration as well as deceleration. Overall, they are much more efficient dynamically with almost 250 grams reduced from the outermost section of the rim profile.
We do love the quick engagement from the rear hub, and it is a real advantage if you are racing. Most of all when there is the on and off power situations like coasting in a draft to responding to an attack. For those who are holding steady power and never really coasting it is a mute benefit but still nice to have. Overall, the hubs have been great, and Zipp offers a freehub for XDR, Hyperglide and Campy.
If you roll up to a ride on these 80mm deep wheels, someone is bound to assume you got a new bike. They completely transform the aesthetic of every bike we tested them on and were guaranteed conversation starters. The deep profile definitely alters the feel of your bike at speed, with a more stable sensation. They also act as reminders to turn with your hips and weight, not your bars.
Speed is your friend with the 808 Firecrest, and the new lighter weight makes them a great option for the hardcore racer that knows the speed will always be high. For those that aren’t always pushing the pace, they might not be the best option for windy mountain passes.
The deep section wheel does deliver more of a speaker effect when you shift, amplifying drivetrain noise. If your bike is tuned perfectly, it’s not a big issue, but if it’s a bit off, you will be constantly reminded. Squeaky disc brakes have a similar effect, but we didn’t notice it as much as the shifting noises.
The tubeless setup and performance were top-notch, but the hookless bead means you must use a tubeless tire at all times. We don’t see this as an issue since most modern tire companies have realized it is the future and are producing plenty of quality options. The biggest change most riders traditionally minded riders will need to make is tire size and pressure. 75psi is the absolute max no matter what tire size is chosen.
Will you see us running the 80mm deep 808s on every ride from here on? Probably not. However, with the huge reduction in weight, we won’t be surprised to see more of them at the local races and zesty group rides. For those interested in the absolute pinnacle performance from Zipp in super deep wheels, check out the new Zipp 858 NSW. They have an undulating 82mm-85mm deep rim shape and have an impressive claimed weight of 1499 grams. They also come with a hefty price tag of $4400.
- Impressively light for 80mm
- Watch out for wind gusts
- Hookless and wide for modern tubeless
Weight: 1663 grams (with tubeless tape and valves)
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