Lightweight disk wheels are the lightest in the world, starting at only 700 g for a rear wheel. However, due to their unique design which utilizes the full potential of the fibers they are immensely stiff and long-lasting. They are recommended for time trials, triathlons and track racing. Read on to find out why they are so strong yet light at the same time.

Lightweight disk wheels are unique in that they are the only wheels in which the carbon fibers are oriented perfectly in the direction of the forces to be transmitted. All rotating forces originate at the hub and have to be transmitted to the tire. The lateral forces originate at the contact patch of the tire and must be transferred to the hub. Carbon fibers can only transfer forces if they are positioned in the direction of the load, as they can only transmit pulling forces. In this regard they behave like ordinary wire spokes.

Traditional disk wheels

» The fibers run in a straight line across the entire wheel. Only few fibers connect hub and rim. Thus, most fibers transfer neither torsional nor lateral loads. Well-positioned fibers are marked in white; other fibers are marked in shades of grey.

Traditional disks use mats of woven carbon (see picture). Disadvantage: only a fraction of the fibers run in the desired direction from the hub to the rim. Most fibers just cross the wheel and connect two spots of the rim without ever touching the hub. Power and lateral loads are transmitted very poorly. Thus, lots of material is needed to make the wheel strong enough to withstand the forces encountered in professional racing. The result is a heavy wheel (1400 g and up). In the picture on the left, well-positioned fibers are marked in white; other fibers are marked in shades of grey.

The “improved design”

» Compared to above, more fibers connect the hub to the rim. However, most fibers still run towards other fibers, making them useless when it comes to the transfer of loads. Again, well-positioned fibers are marked in white; other fibers are marked in shades of grey.

This design is improved by using several segments of carbon fiber mats (see picture). These wheels usually do not have a smooth surface. More fibers now run from the hub to the rim. However, many fibers still run towards other fibers instead of to the hub. Since by principle no fiber can transfer loads applied from the side this design again wastes a lot of material and weight.

Nobody in their right mind would ever build a spoked wheel following the design of these disks. Common sense tells us that all spokes must run from the hub to the rim. Spokes fixed to two sides of the rim without ever touching the hub make no sense at all.

Equally, no sane wheel builder would ever copy the “improved design”. If he did, he’d have to fix some spokes to the hub and the rim and then fix one end of the other spokes at the rim and the other to the middle of another spoke. Have you ever seen such a wheel?

» Design utilizing the full potential of the material: All fibers run tangentially from the hub to the rim. There are no fibers crossing the wheel in other directions.

» All fibers run in the direction of the loads encountered in race situations. No ordinary carbon fiber mats are used.

Lightweight disks are designed like spoked wheels: Many carbon fiber threads connect the hub to the rim. The threads leave the hub shell tangentially – in the direction of the forces to be transmitted. No ordinary carbon fiber mats are used. Our sandwich design uses no fibers that transfer no loads. The result is a wheel which is both stronger and lighter than other disk wheels. Who says you can’t have it all?

Concave shape of our disk wheels

The two sides of our disks are not parallel planes, but slightly concave. Tests have proven this to be the superior shape, producing less drag. In addition, the wheels are made stronger as the whole width of the hub is used to support the wheel.

The Hubs

We use modified Shimano Dura Ace hubs. These are available as a 9/10-speed freehub for use with cassettes or with threads for track cogs. A Campagnolo 9-10-speed version will be available in the summer of 2004.

Carbon brake surface

» To prevent thermal problems, the brake surface is made from extremely robust carbon fibers.

The brake surface is made from carbon fiber as well. Together with special brake pads suitable for carbon rims our wheels deliver excellent brake performance. Aside from being heavier, aluminum rims would create other problems: As aluminum expands at a much greater rate than carbon fiber when heated, the rims could separate from the rest of the wheel, making the rim unsafe to ride in the long run.

The sandwich construction

The spoke threads are wound around two thin foam cores. As a last step, a thin white layer is used to cover the entire wheel. The top layer does not transfer any weight, which is why it can be kept very thin. This saves weight and in turn multiplies the types of competitions our wheels are suitable for. Please handle the wheels with care to avoid harming the finish.