Making up about 50% of your total race time, the bike portion of
a triathlon is where equipment choices can make the difference
between first and fifth, and no other equipment choice will save
you more time than a disc wheel. While traditionally-shaped disc
wheels are faster than their spoked counterparts, the Roval 321
Disc for disc brakes turns conventional design on its head,
creating the fastest wheel on the planet.
Disc wheels often fall into two categories-a completely flat
shape, with structure coming from carbon fibre and a honeycomb-foam
filling, or a spoked wheel that's been faired with a carbon fibre
cover. In our quest to break traditions, the 321 uses a single
layer of 1k carbon fibre on each side of the wheel, and it all
comes together at the brake track bridge. This kind of carbon fibre
is rarely used in bicycle components due to its high manufacturing
cost, but it offers a bevy of performance benefits. This coveted
carbon is much lighter than other layups, like 3k and 12k, and it
can only be laid by the most skilled of carbon fibre craftsmen.
It's complicated, but the pay-out is worth it, as it delivers a
supple ride and one of the lightest disc wheels available. And in
the real world, this means that it'll spin-up quickly and reduce
fatigue over the length of the course.
Stiffness is often the "hot-topic" in the disc wheel world, but
we think it's an interesting conversation. It's long been thought
that efficient power transfer and high stiffness are directly
correlated, but through extensive field-testing, we've determined
that this isn't the case at all. In fact, our initial disc was so
stiff that, under power, it wouldn't flex with the frame and this
caused brake rub. This wrongly creates the perception of a flexy
wheel, when really, the wheel is actually too stiff. In order to
solve the brake rub problem, we first designed our optimal aero
shape and then worked on our internal stiffness targets to fit
within what we consider to be a desirable frame stiffness.
And while light overall weight was a development priority, our
focus was aerodynamics. Through hours of Computational Fluid
Dynamics (CFD) and testing in the Win Tunnel, we developed a
never-before-seen shape that's optimized to work with a tire for
on-bike airflow. What this translates to is an all-carbon disc
wheel that, on the non-drive-side, has a shape that's as
aerodynamic as our current understanding allows, and a drive-side
shape that's as aerodynamic as the wheel-dish and derailleur
clearance will allow for.
To save every possible watt, we've also added CeramicSpeed
bearings and DT Swiss 240 hub internals into our hub. Each 321 Disc
wheel is also 2Bliss Ready right out of the box and comes with a
padded wheel bag, quick-release, and tubeless valve stem.
Designed for the most uncompromising athletes in the world, with
engineering to match, the 321 Disc is the world's most advanced
disc wheel for your race against the clock.