On the fifth stage of the UAE tour, Lotto Dstny rider Thomas De Gendt’s front tire blew off his rim. Reports indicate that the blowout occurred due to an incompatibility between the hookless rim design of the Zipp 353NSW wheels and the 28mm wide Vittoria Corsa tires De Gendt was using. This incident caught my attention because I too use hookless Zipp 303S wheels, and the idea of my tires unexpectedly detaching from the rims was troubling to say the least. So I decided to look deeper into the differences between hookless rims and traditional ones.
Hookless rim technology has been in use for several years. Unlike traditional wheels that rely on a hook to secure the tire bead, modern tubeless technology requires only a straight sidewall.
Hookless rims offer numerous advantages. Eliminating the hooked sidewalls reduces manufacturing expenses, enhances wheel durability against impacts, and increases the effective internal width. This allows the tire to sit snugly against the wheel, improving aerodynamics of the overall bike. The adoption of hookless technology has been widespread in the cycling market, with companies such as Enve and Zipp opting to exclusively produce hookless wheels.
Despite these benefits, concerns have risen about the safety and compatibility of hookless rims with certain tires. Videos circulating on social media depict new tires exploding off the rim immediately after inflation. Manufacturers have responded by providing more conservative specifications for their hookless wheels, such as recommending specific tires for each wheel and lowering the maximum pressure rating to around 70 psi in order to address this issue.
Thomas De Gendt’s recent accident has drawn attention to the issue of hookless rims. The UCI, the official governing body of cycling, has initiated an investigation into the incident. From De Gendt’s incident, a question arises: will hookless wheels shape the future of cycling, or will there be a return to traditional hooked-style wheels?
