Corima has offered their thick carbon spoked aero wheels before, but not in a disc brake version. And not with a tubeless-ready rim attached. With additional torque forces coming into play with the braking at the hub, they had to rethink the MCC wheel design and create something entirely new.
The result is the new MCC DX and it’s Y-shaped spoke “anchor” for the rear hub. Available in tubeless-ready and tubular, they say it’s the ultimate incarnation of an aerodynamic disc brake wheel. Here’s why…
What’s up with those spokes?
The carbon fiber spokes are handmade in France, as are their rims. They’re a new bladed aero profile, a change from the round profile used on prior MCC models.
The front sticks with their traditional angled-backward-off-the-hub spoke layout, but the rear needed a new design. With disc brakes, there’s a ton of torque generated during braking…torque that can stress the spokes in ways they’re not necessarily designed to handle.
Their front layout worked out fine, but in the rear, the original design was there to handle drivetrain forces…which are opposite of braking forces. So, they came up with the Y-shaped anchor (which is a terribly heavy sounding name for the part, but it, too, is made of carbon fiber). This handles the torque in both directions.
But those spokes are so thick, how is it aero?
True, they’re big. But there are only 12 of them. And from a crosswind’s point of view, their nearly-paired placement means the wind sees more like six spokes. Corima says the new designs yield a 9% drag reduction up front, and 18% in the rear.
They’re bonded without tension, which is a patented feature unique to Corima. They say this improves durability of the wheel because the spokes aren’t constantly pulling against each other. Because carbon doesn’t stretch, they stay laterally stiff. And, should you break a spoke, the wheel won’t snap out of true.
The MCC rim brake variants will continue on in the line, and those should get the new aero spoke shapes, too.
Corima finally goes Tubeless-Ready…why so long?
Nevermind that there’s still not a formal Road Tubeless standard, but when you have a unique (and patented) rim design that uses a structural foam core inside the rims with a carbon torsion bar, you have to do things differently.
Corima’s new tubeless-ready rims use a small channel near the bottom of the rim profile (where the spokes come out) to allow any air and sealant to escape through a check valve. This was key to preventing sealant, and thus air, from getting trapped inside the rim cavity and potentially pressurizing and damaging the rim. They require rim tape, and strongly recommend making sure they’re taped really, really well.
A deep center channel makes tires easier to mount. And they use a small bead hook, so you can comfortably run higher air pressures.
Corima MCC DX Specs, Weights & Pricing
Rim width for both the tubular and tubeless, in both the 32mm and 47mm depths, is 26mm external, 19mm internal. The Tubeless-Ready caimed weights below include preinstalled rim tape and valve stems.
- MCC DX 32mm Tubular: 1,285g (550/735g) – US$4,000 MAP
- MCC DX 47mm Tubular: 1,355g (585/770g) – US$4,200 MAP
- MCC DX 32mm TLR: 1,435g (650/785g) – US$4,000 MAP
- MCC DX 47mm TLR: 1,535g (675/860g) – US$4,200 MAP
Max tire pressures are:
- 23mm tire – 7.5bar / 108 PSI
- 25mm tire – 7bar / 101 PSI
- 28mm tire – 6.2bar / 90 PSI
- 30mm tire – 5.7bar / 82 PSI
They’re in production now. They should be shipping globally by late May/early June, with select markets possibly seeing a few earlier.
But wait, there’s more (affordable) wheels, too!
Want the same MCC rim at a lower price point? Try the WS+ and WS series wheels. Both sets share the same carbon rims as the MCC wheels, but they differ by type of hub and spokes…and braking.
The WS+ Family uses a higher end carbon hub with straight pull spokes, but is only available in rim brake options for both tubular and clincher. Retail is $2,300 (32mm) to $2,500 (47mm/58mm) regardless of tire type. For now, only the 47mm gets the new TLR rim, the other two depths are standard tube-type clinchers.
Buuuuuut, all of Corima’s carbon clinchers will transition to TLR designs, it’s just a matter of them being a small French manufacturer and TLR will be phased on the next production runs.
Their “entry level” family of wheels are the WS. They use alloy hub bodies and J-bend spokes, but the exact same rims as the MCC and WS+. TLR rims are currently only available in the 47mm depth, but like the WS+, other depths will be TLR soon enough.
WS-series wheels retail for $2,000 (32mm) to $2,200 (47mm/58mm) for tubular or clincher/TLR, and all depths are available in rim- or Centerlock disc-brake variants.
Claimed weights coming soon. Available to order now, shipping and delivery expected late May/early June.
