Lost in the announcement was a little detail buried in the eligibility rules pdf document that many racers with modern equipment may celebrate. The 35mm tire width restriction is changing.
A Narrow View on Tire Widths
First, a bit of history. How did we get here?
Ever since the UCI implemented its narrower tire width rule in 2010, we’ve questioned the motivation behind USA Cycling also following suit.
The UCI claimed it was trying to make cyclocross more affordable, yet seemed to penalize those with the most-constrained budgets who might ride clinchers or tubeless and need the extra air volume. Pros and tire companies lamented the changes, but USA Cycling jumped on board with the 33mm maximum.
Amateur racers, led by a petition from Norcal’s Paule Bates, swayed USA Cycling to add 2mm to its maximum width for amateur (non-UCI) racers.
Yet since 2010, rims have gotten 50% wider and tubeless tires have become the dominant option and wider tire options abound, especially with the popularity of gravel.
The rule has confused many racers who ended up worrying about tire widths at local races.
On a 22.5mm internal width rim, the 33mm original Specialized Terra fails a UCI and USA Cycling (Nationals) tire width maximums, and for most retail-paying customers, that’s a great thing. 36 mm at 30 psi. © Cyclocross Magazine
While Nationals racers stressed about legal tire widths, USA Cycling largely didn’t enforce its tire width rule after 2010. We asked the governing body about the unenforced rule in 2018 heading into Reno, and published Brandon Grant’s Op-Ed on blowing up the rule in 2019, and will take the blame for recent enforcement in 2019 Lakewood, Washington, albeit with a plastic block that the official admitted was flexible and forgiving.
Unfortunately, racers found new cyclocross tires and even off-the-shelf bikes with stock tires and tubes were failing the 35mm restriction.
Check your rim and tire width before lining up for Nationals. The new Michelin Mud inflated above 35mm on a 23mm internal width rim. The latest Michelin Power Cyclocross Mud tubeless clincher tire. © Cyclocross Magazine
More Volume, More Wiggle Room
The good news is now USA Cycling has added 3mm to the width, accomodating wider rims that come on bikes, and the newer crop of mixed terrain and higher volume cyclocross tires many spend all season on.
With newer rims now coming as wide as 30mm (internal), compared to the 13mm clinchers we riding just a dozen years ago, racers have a chance of running the current crop of cyclocross tires on their rims and still racing Nationals.
They also have a chance of running some of the higher-volume cyclocross tires like the 38mm Ritchey Megabite and 38mm Specialized Terra, two of our favorites for year-round, all-conditions riding.
38mm Ritchey WCS Megabite tubeless cyclocross clinchers are some of our favorite tires, and now have a chance of being Nationals-legal. © Cyclocross Magazine
The new rules apply to Masters, Collegiate and Singlespeed, and now includes the following language:
Modified UCI regulations. Double triangle frame construction, traditional CX bike with maximum 38mm tire width.
The 38mm Specialized Terra is an aggressive high-volume tire that now might be USA Cycling Nationals-legal on some rims. © A. Yee / Cyclocross Magazine
Of course, USA Cycling is playing catch-up with these new rules, and the high-volume cyclocross tires on wider rims are likely to fail. However, at least the 33mm tires on modern rims have a chance of passing. That’s some progress.
2020 USA Cycling Cyclocross Nationals Eligibility Rules
You can read the updated rules in USA Cycling’s document below. The tire width change is on page four.
2020 USA Cycling Cyclocross Nationals Eligibility Rules Tire Width
