Hunt’s Limitless Aero project has been on our radar for more than a year and a half. But now we finally have all of the details on what Hunt says are “the world’s fastest road disc brake wheels up to and including 50mm” of depth – the same wheels ridden this spring to set a Strava KOM record on the brutal cobbles of the Trouée d’Arenberg, one of the toughest pavé sectors of Paris-Roubaix.
Hunt 48 Limitless Aero Disc wide tubeless carbon road wheels
We’ve been following along with the Limitless Aero wheel project since last spring when we caught up with Hunt in the GST wind tunnel. We then reported on them last summer at Eurobike before they had a final name. Developed entirely in-house by Hunt’s own aerodynamics engineer Luisa Grappone, the idea was always to create the best aero road wheelset for how we actually ride road bike now. That meant disc brakes were a no-brainer, but also that wide tires were a must. The wheels were to be designed to deliver peak aero performance with 25mm AND 28mm tires.
Aero road wheels, but for wider modern road tires
Most modern aero wheels lose much of their aerodynamic benefits when you put on anything wider than a 25mm tire. And when riders want a 28mm or 30mm tire, those gains are usually all gone because the wider surface of the tire determines the aerodynamics more than the rim that is in the shadow of the tire.
Obstacles to going aero AND wide
There are a few big obstacles to optimizing aerodynamics for larger tires. The first is that to make wide tires aero, you need wide rims. The simplest way to do that is increasing both inner & outer rims widths, which has the least impact on making the rims heavier. But if you do that, once you get out to 24mm or 25mm inner widths, you lose compatibility with even 25mm tires, and definitely lose a 23mm option. You also can’t go wider than around 28mm external with rim brakes, so thankfully discs are winning out in the long run.
Hunt chose to keep a 22.5mm internal to maintain compatibility, with 23-30mm tires (compliant with ETRTO’s as yet unreleased Tubeless Road Standard), which meant they needed to just increase the outer rim width. Hunt’s time in CFD and the wind tunnel settle then on an ultra-wide 34.5mm overall outer width to maintain optimal aero performance with big tires.
Hunt’s patented multi-part Limitless aero rim construction
Now normally that would be very problematic from a weight perspective. The 12mm difference between inner & outer widths would mean seriously heavy rim weights, so Hunt spent the last year developing a solution that kept a regular width tubeless ready bead, but added a strong low-density polymer that completes that ideal wide, 48mm deep blunt aero rim profile at 44% of the weight of carbon.
(The low-density polymer is the black section above; fitting into the open channel in the image below.)
Doing so allowed Hunt to keep a reasonable wide 22.5mm internal width, a super wide 34/5mm external width for optimal aero performance with 28mm tires, plus overall light weight (1582g claimed for the complete wheelset) and even added rim strength in the end. The whole process makes the Hunt 48 Limitless Aero Disc rims truly unique, and resulted in a new exclusive patent owned by the core management team of Hunt.
Are the Hunt 48 LAD wheels really the “World’s Fastest”?
There are always tons of claims in the bike industry about how one aero product is faster than the next. Hunt knows that too, so they’ve tried to be totally transparent about how they make those claims. A full technical white paper is available that details their research protocols for wind tunnel testing methodology, including data/graphs and the full range of wheels that were tested against. Read it for yourself here.
So what does that mean for the wheels you can ride?
The result of all the technical development is a reasonably-priced, aerodynamic disc brake tubeless carbon road bike wheelset. Selling for £1289 (~$1650 / 1450€) the Hunt 48 Limitless Aero Disc (48 LAD) are actually still a fraction of what premium aero wheels from some of the biggest brands in the industry build.
And at the same time, Hunt says their 48 LAD wheels have significantly lower drag when tested with 28mm Schwalbe Pro One tires across a wide range of yaw angles. That’s pretty easy to believe when you see that only the Hunt rims are substantially wider than the 28mm tire itself.
Hunt 48 LAD wheel build details
The new “world’s fastest” road disc wheels get a solid build setup at that price. The wheels are laced up with Hunt’s straightpull Sprint Disc hubs using FastEngage 7.5° freehub bodies fast with 48 points of engagement. And those spin fast & smooth on premium CeramicSpeed hybrid ceramic bearings. Interestingly enough, the Danish bearing specialist reached out to Hunt to collaborate on their Limitless wheel project. The centerlock 7075 alloy hubs are standard with 12mm thru-axles (with pretty much every axle standard available) and offer Shimano, SRAM XD or XDR & Campagnolo freehub bodies.
Wheels are built up with Pillar’s latest Wing 20 butted & bladed aero stainless steel spokes that are actually a diamond-shaped aerofoil blade, optimized for aerodynamics across a wider range of wind yaw angles than conventional flat-bladed spokes. Interestingly, Hunt laces the disc brake 48 LAD front wheels 2x with just 20 spokes, while the rear sticks with a more common 24 spokes, again 2x.
The 48 LAD rims are rated to a max pressure of 100psi for 25-28mm tires (substantially lower when you go to 30mm of wider.) Hunt says the wheels are suitable for 23-50mm wide tires, with 25-28mm delivering peak aerodynamics. Like all Hunt wheels, when you order them, Hunt will also sell & install a wide selection of tubeless tires with sealant, so you don’t have to deal with the hassle or setup mess.
Hunt wheels are warrantied for 3 years from purchase (6 years for those CeramicSpeed bearings), and are rated for rider+bike of 100kg.
Pricing & availability
Like most of Hunt’s new wheels the claimed 1582g Hunt 48 Limitless Aero Disc are being offered first as a pre-order now for delivery by the end of July 2019. You can either pay a £99 refundable deposit of the full £1289 now, direct to Hunt’s web shop. Global free shipping on Hunt wheels is included in that price. So what’s stopping you from rolling on the new “world’s fastest” road disc brake wheels?