Wheel brand Swiss Side has released an open letter to the UCI objecting to the recently proposed rules that would ban rims taller than 65mm in UCI road races.
Swiss Side’s letter requests “an urgent reconsideration of the recent change to the equipment regulations implementation”.
Last month, the UCI announced sweeping revisions to its technical regulations, which are set to come into effect next year and are aimed at improving rider safety.
The changes include limiting rim depth to a maximum of 65mm alongside a minimum handlebar width of 400mm, which experts have called “discriminatory”.
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An unexpected and extremely costly blow
Swiss Side says in the letter that learning of the rule change through the press two weeks before the launch of its 68mm-deep Hadron Ultimate 680 wheelset “was a major and unexpected and extremely costly blow”.
Swiss Side says that its wind-tunnel and on-road testing, alongside rider feedback, found the new wheels to be more stable in crosswinds than some shallower rims.
“Through the objective measurement of the steering moment, we can firmly state that rim depth has far less influence than tyre width, tyre tread pattern (and its effect on the aerodynamic characteristics), and the steering geometry of the bike frame (steering axis angle and trail),” the letter reads.
“Furthermore, the rim shape and depth are the parameters which enable tuning the handling characteristics of the wheel. Deeper rims, apart from having more mechanical stability due to the increased rotating inertia, also allow for better tuning of the aerodynamic and handling characteristic[s] of the wheel.
“A poorly engineered rim shape or the wrong combination of rim shape and tyre, can lead to a very unstable, unpredictable and potentially unsafe aerodynamic characteristic, regardless of the rim depth,” it says.
Swiss Side says the purpose of its letter is to show the importance of an “objective, science-based approach” that should be part of implementing equipment regulations.
“The recently proposed limitation on the rim depth to 65mm for 2026, can be objectively shown with regards to the steering moment, and the front wheel handling characteristics, to be ineffective and even counterproductive in bringing any improvement in wheel stability and thereby rider safety,” the letter says.
Inadequate notice
Swiss Side says it takes the company two-and-a-half years to develop a high-end wheelset. This is due to project preparations including research and market analysis; aerodynamic development; engineering and industrial tooling design; prototyping; and final production.
It says the sum of this process can be six figures, which it aims to recoup over a four-year period. Therefore, Swiss Side calls the six-month notice on equipment changes “inadequate”.
“The UCI’s unilateral decision to limit rim depth to 65mm, without a justifiable, quantifiable, and meaningful impact on safety, with only 6 months’ notice, has a direct and negative impact on the entire supply chain and ultimately, on the end consumer. They, including the amateur and professional cycling teams, are suddenly and unexpectedly left with products which they can potentially not use in UCI road racing in less than 6 months’ time.”
“The financial implications for the entire supply chain, all the way down to the end consumer, are enormous,” it says.
Swiss Side calls for “meaningful change and responsible governance from the UCI, by including the cycling industry, and in particular experts in the relevant fields, as part of the decision-making process”.
