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Profile Design is a company better known in triathlon and Ironman circles, but last year it launched the brand new Twenty Four carbon fibre wheels, available in a choice of three rim depths and tubular or clincher configuration. I've been testing the shallowest of the three rims, a 38mm carbon clincher wheelset priced at £1,249.95 and offering some very good performance for the money. There's a lot of choice in the carbon clincher market right now, and these are a very viable alternative.
Profile Design offers a choice of three rim depths, 38, 58 and 78mm, and you can mix and match the rims - Profile sells individual wheels unlike most companies that only sell them in pairs. I tested a matching pair of 38mm wheels, because I really like the ride of a shallower rim and with the advance in aerodynamics means you're not losing out too much, but also gaining a lighter wheelset. It's a good rim for daily riding in the changeable UK weather.
The Profile wheels get their name from the new 24mm-wide rim the company has developed itself. Profile used Computational Fluid Dynamics (CFD) to design its own unique rim shape, and used real-world course data from triathlon and Ironman races, supported with wind-tunnel testing, to settle on a rim shape it felt provided the best aerodynamic performance.
It's clear, once they're fitted to a bike, that these are fast wheels. In a straight line, the pace is very impressive, and they hold speed very easily making high speed cruising a very enjoyable experience. As with all aero products, it's tricky accurately testing them without access to a wind tunnel, but in comparison testing to other carbon wheels, they demonstrate good pace.
The wheels are also very good in crosswinds, which is a good thing because there are plenty of crosswinds where I ride. Riding very deep section wheels can prove challenging and not very enjoyable but the Profile Design wheels managed the airflow when coming from the side very well, with a stability lacking in many deeper section wheels. There was no violent or sudden tugging when riding along exposed roads, making them very usable, they would be ideal as an everyday wheelset or for UK sportives and road races.
The rims are manufactured from Japanese carbon fibre with a proprietary high Tg resin used for the brake track, which is rated up to 220°C. Profile says it has use a patented process to manufacture the brake track, bead and rim bed which produces a more uniform rim with fewer voids present in the carbon. Profile has developed its own brake blocks and claims braking distance is reduced by a whopping 28% compared to its previous Altair wheels.
Braking performance is a critical aspect of a carbon fibre wheel, and as fast and aerodynamic as a wheel might be, it's really important that the brakes work well, especially when you have to deal with errant road users and, around my way, dozy pheasants. With Profile's own brake blocks fitted, the braking performance was highly impressive, on a par with the best carbon fibre wheels on the market. There's plenty of power available and is consistent and progressive, so you can control the available power very easily. They also work well in the wet too, but there's a noticeable drop in bite but they work better than some other carbon wheels in the rain.
The wheels are handbuilt using Sapim CX/Ray spokes and Polyax Secure+Lock nipples, with quality control throughout the build process. Profile's own hubs use a straight pull spoke design to improve aerodynamics with 6061 T6 aluminium hubs with a 7075 T6 aluminium freehub body, and sealed cartridge bearings.
Profile thoughtfully supply the wheels in smart wheel bags with brake blocks, the minimum you would expect when buying a set of wheels, but the company goes a step further - you get tyre levers and even spare spokes.
As well as good aerodynamics and braking performance, the wheels are very responsive, with a high level of stiffness noticeable when sprinting out of the saddle or climbing hard, there's no unwanted sideways flex. They feel direct through the corners, and over bumpy roads they're surprisingly comfortable. A benefit of the wider rim is that they work really well with 25mm tyres, with the broad rim shape pushing the tyre beads further apart for more support something you can detect as a benefit through hard cornering.
Very good carbon fibre clincher wheels with good aerodynamic and braking performance
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Make and model: Profile Design 38/TwentyFour Clincher wheels
Size tested: 700c
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
The Profile Design 38|TwentyFour Series Carbon Clincher Wheelset was born out of the necessity for increased speed, improved aerodynamics and better stopping power. Profile Design used Computational Fluid Dynamics (CFD), wind tunnel testing and course modeling to handcraft a wheelset that accelerates, handles and stops with phenomenal performance. Precision engineered from proprietary carbon fiber that has been laid and shaped for strength and aerodynamics, the 38mm deep rims raise the bar on lightweight and affordable high-performance race wheels. Remember, you get what you pay for...in the case of the Profile Design 38|TwentyFour Series Carbon Clincher Wheelset, it'll definitely be money well spent.
Tell us some more about the technical aspects of the product?
Specifically formulated to withstand the same heat our rims can take on, our brake pad compound is exclusive for TwentyFour Series wheelsets. Using a specially formulated rubber compound, durometer and friction agent, we developed a proprietary brake pad and reduced braking distances over that of other carbon fiber wheelsets.
TwentyFour Series hubs are forged from 6061-T6 Aluminum then precision machined with a tolerance of 100th of a millimeter increasing durability, strength and stiffness. The freehub body is machined from 7001-T6 Aluminum then shot peened hard anodized to create an 18% increase in material strength compared to standard aluminum freehubs. This prevents the cassette from digging into the freehub body resulting in better shift performance and increased power transfer.
Wind tunnel tests can tell us how fast wheels are at different angles of attack – but how common are these angles in the courses most important to our athletes? Blindly applying tunnel data to the unpredictable force of Mother Nature did not add up to us. We took our tunnel data a step further, and worked with SpeedTheory to break down popular road and triathlon courses into thousands of segments, mapping the performance of our wheels against historical wind speeds, angles and race day conditions around the world. TwentyFour Series wheels continue to come out with distinct advantages across the yaws most commonly encountered not in a lab, but in the real world.
CFD Engineered Rim Profiles
We designed, tested and revised hundreds of rim shapes to find the very nuances that affect crosswind feedback and handling. Partnering with a team of technicians specializing in Computational Fluid Dynamics from golf equipment to race cars, we were able to merge their expansive CFD knowledge with our aerodynamic expertise. Manipulating width, width location, depth and conicity, we sorted through months of generated data to select the highest performing rim profiles.
Precision-Engineered Materials Every Step of the Way
Rather than use the consistently failing attempts at reducing the temperatures produced by braking, we rejected what has become acceptable practice and instead increased the heat capacity of our materials. Our proprietary high Tg point resin is 30% higher than other 'high' Tg resins. A rim that can withstand more heat leads to braking performance unseen on other carbon rims.
There's a lot of choice at this price with carbon wheels getting more affordable, but these Profile Design wheels offer a premium performance at a very competitive price.
Tell us how the product performed overall when used for its designed purpose
I was really impressed with the performance in all areas when compared to other wheels, even wheels costing a lot more money than Profile are charging.
Tell us what you particularly liked about the product
Really good performance and a competitive price.
Tell us what you particularly disliked about the product
Isn't really anything to dislike, they do everything really well.
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
Anything further to say about the product in conclusion?
A really capable and high performance carbon fibre wheelset at a good price.
Age: 31 Height: 180 Weight: 67
I usually ride: My best bike is:
I've been riding for: 10-20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: road racing, time trialling, cyclo cross, commuting, touring, mtb,
David worked on the road.cc tech team from 2012-2020. Previously he was editor of Bikemagic.com and before that staff writer at RCUK. He's a seasoned cyclist of all disciplines, from road to mountain biking, touring to cyclo-cross, he only wishes he had time to ride them all. He's mildly competitive, though he'll never admit it, and is a frequent road racer but is too lazy to do really well. He currently resides in the Cotswolds, and you can now find him over on his own YouTube channel David Arthur - Just Ride Bikes.