FLO Cycling 64 AS Disc – Wide Speed Riding Well Above Its Price

There was a time when carbon wheels were only for the pros or those with lots of disposable income. But times have changed, and carbon hoops are accessible to just about anyone that wants to run them. The great thing too, you don’t have to save them for race days only. FLO Cycling has a great lineup of road and gravel carbon wheelsets that will perform on race day but are dependable enough for everyday use.

The All Sport lineup contains the 49 AS, 64 AS, and 77 AS. Each number references how tall the rim is in millimeters, giving you options for climbing days, all-around days, and all-out speed days. Each has an external rim width between 28.3-28.8mm and an internal width of 21mm, meaning these wheels are made to run the wider tires we are seeing on the road these days.

When FLO set out to design the All Sport line, they took the holistic approach of the wheelset as a system, not separate components of a hub, spokes, rims, and tires. This allowed them to design that includes the tire as part of the aerodynamic equation. Specifically, they used the Continental GP5000 in a 28mm width. They felt it is the perfect balance of speed, durability, comfort, and aerodynamics.

Instead of starting with aerodynamics, they looked at rolling resistance first. While you would normally think of the tire as the main component of rolling resistance (which it is), FLO looked at how the internal rim width played a part in the shape of the tire and how they could use it to reduce the rolling resistance as much as possible. After deciding the 28mm was their sweet spot, they designed the aerodynamic profile of the rim around the tire and its shape.

Next up was deciding on the depth of the wheel. In testing profiles and heights, they found that the deepest wheel wasn’t always the fastest, especially when considering crosswind stability. When looking at data from computational fluid dynamics (CFD) tests and real-world data collected, 49mm was the best for the 40-49mm range, 64mm for the 50-65mm range, and 77mm for 65-90mm range. In final testing, the 77mm wheelset actually is faster than their previous 90mm wheelset that the AS line replaces, while remaining more stable in crosswinds.

The final piece of the puzzle was carbon layup, and tire pressure charts, something you don’t always see wheel manufacturers put time into creating. Vibration is not your friend when riding as it reduces traction and makes for a less confident, less enjoyable ride. FLO optimized their carbon layup to act as a leaf spring and reduce the vibration felt by the rider, while the optimized tire pressure guide helps you smooth out rough surfaces and keep the tire planted on the road.

So that’s a lot about the overall lineup. FLO has a great blog series talking about all of their wheels and doing deep dives into aerodynamics, rolling resistance, and many other parts of wheel design, testing, training, and even economics. If you want to geek out, I highly recommend going down that rabbit hole when you have time to kill.

When the boxes arrived at our east coast service course, we had a set of 64 AS Discs for our Van Dessel Motivus Maximus LTD test rig, and the new G700 Disc for the Van Dessel Full Tilt Boogie. I’ll have a separate article for these deep gravel wheels that have been a game-changer for me.

When talking to FLO about a review, we settled on the 64 AS Disc since it is a sweet spot for speed and climbing. It might not be the optimal model in the lineup if you want to focus on one or the other, but it blends the best of both worlds if you encounter both. And that is exactly what I found.

Fitting the wheels was straightforward. Setting them up tubeless was a breeze with the included tubeless tape and valve stems, using my Topeak Joe Blow Booster and a set of Continental GP5000 TL’s in 700×32. With Effetto Mariposa Cafelattex sealant, they have been holding air effortlessly for months, with just a need to top them up before a ride. The FLO Vortex 3 hubs accept CenterLock discs and are built up with 24 Sapim CX-Ray spokes front and back.

On the bike, they look incredible. The 64 AS Disc is one of the deepest wheels I’ve run, beating out the 3T Discus C60 and Vision Metron 55SL. They are also one of the wider wheels I’ve ridden, especially when it comes to carbon road wheelsets. The 32mm wide GP5000 TL’s measure out to 32.5mm, which fits nicely on the Motivus Maximus. The width might be a little overkill for road riding, but I appreciate the flexibility to take the build onto light gravel sections.

On the road, the 64 AS Disc shines. If you read some of the blog posts from FLO, you’ll understand their obsession with aerodynamics, but it is more than speed. The width and shape of the rim help keep them stable in crosswinds, which is something important for a 60mm+ tall wheelset. At 6′ and 190lbs, the wheels felt very stable in crosswinds, only catching me out a few times with major gusts that would have caught even a pro by surprise. Lighter riders might feel it a little more, but the attention that FLO has paid to stability really shows.

Speed is another factor. I mean, if you are going to put wheels on that are this deep, going fast is one of your goals. I don’t have a wind tunnel to test them in, but through a few thousand miles of riding on them, there is definitely an aerodynamic benefit that helps you get up to speed quickly, and hold it. I’ve set many Strava segments with them, both flat and uphill. Whether it is straight-line speed, or ripping through corners, the FLO 64 AS Disc and Continental GP5000TL was confidence-inspiring to continue to keep pushing for more and more speed.

Climbing is another thing to talk about. While they might not climb quite as fast as the 49 AS Disc, unless you are doing a dedicated hill climb, or spending the days pointed upwards in the Alps, the 64 AS Disc took every climb I could throw at it. The wheels are stiff to help put the power down, but not overly heavy at an actual 1770g for the set. In fact, they are only about 48g heavier than the 49 AS Disc for a 15mm taller rim. I’ve always been happy to give up that tiny amount of weight to gain an aerodynamic advantage when on the flats, which makes for an overall faster ride in my opinion.

Comfort is the one area that was hard for me to quantify, especially because of riding the 32mm GP5000 TL’s. The super supple casing of the tires, larger volume, and being run tubeless, all make for a super smooth ride on all types of pavement. The wheel/tire combo never felt harsh though, and have only been taken off the bike to get other wheelsets on for a review, or to move to my gravel/CX Van Dessel Full Tilt Boogie for days I wanted to take that on the road. I liked them so much, that I ended up purchasing them from FLO. Whether it is an upcoming Crit, a long-distance duathlon, or a charity century, the FLO Cycling 64 AS Disc is my go-to wheelset.

When you buy a set of wheels from FLO, it’s more than just buying wheels. You can select from Shimano/SRAM, Campagnolo, and XDR freehubs, and a wide selection of wheels stickers. I went with the black/magenta logo, which happens to match the Van Dessel’s paint scheme perfectly.

Additionally, FLO donates 1% of all sales to their Bike For A Kid program that is run in partnership with the Ironman Foundation. So far, they have donated over 3,000 bikes to get kids riding. For every wheel purchased, they also plant a tree to help offset the carbon footprint of producing carbon wheels. You also won’t find any plastic in the box they arrive in, as they use packaging that is made from 100% recycled cardboard.

At $1,488 per pair, the FLO Cycling 64 AS Disc is a real bargain when it comes to full carbon wheelsets, especially when you look at design and testing that have gone into them, and performance that is well above their price tag.

http://www.flocycling.com