Revolutions and evolutions

The wheel may be a 5,000-year-old invention but designers are still finding ways to make it lighter, faster, safer and more stable.

In recent years, the focus for road bike wheels has been on making the switch from rim brakes to disc brakes. Before that, it was all about refining rim shapes to make them more aerodynamic. Now the market is looking at perfecting the interface between tyre and rim while squeezing out every drop of performance gains in terms of grams shaved and watts saved. Manufacturers are also taking a hard look at their environmental impact and exploring ways of making their products sustainable as well as desirable.

Cyclist talked to some of the industry's leading figures to get an insight into the main changes that are happening in the world of wheels.

Rim widths

The advent of disc brakes not only helped to make road bikes stop quicker, but helped them go quicker as well, and one of the ways it achieved this was by making rims wider.

Jeff Schneider, global head of product at Giant and Cadex wheels, says that the development of wider rim widths was in progress even before disc brakes came along: 'Companies such as Shimano and Bontrager were trying to widen out their rims, but it got to the point where a rim brake calliper just didn't have the leverage.' Now that rims no longer need to pass through rim brake callipers they can be made wider, which means they can accommodate larger-volume tyres without getting a lightbulb' profile shape that can make tyres squirm while cornering. Bigger tyres can be run at lower pressures, which improves compliance, rolling resistance and keeps more rubber in contact with the road for grip. A wider rim also means the transition from tyre to rim is smoother, which can improve aerodynamics.

Tom Marchment, product manager at British brand Hunt, says the increase in rim width has fundamentally improved rider experience: "There has been a far larger increase in the percentage change in rim width than tyre width. So you're getting more support at the base of the tyre.