Mike Macdonald posted a blog post

December 21, 2017

35 mm CX rule

Just a friendly heads up to fellow CX riders re: 35mm max tire width for Masters at upcoming CX Nats in Reno...per Chuck Hodge, USAC Vice President of Operations, "we will be enforcing the 35mm actual width for the Masters events as we have done in the past."IMO, if you plan to run tubeless tires, check 'em good. In my experience. a 35 mm sidewall-listed tire will puff out to 35-40 mm, depending on the particular tire and rim configuration. So...in order to run tubeless, I guess I'll need to buy 33's and hope they don't puff to beyond 35.I find this to be pretty maddening and, hopefully, USAC can find a way to constructively consider tech development when writing/revising the rules.Also...from a mech friend...The tool (normally) used to check is a "gap tool" set to 35 mm. If inserted over tire and lifted and: bike stays on ground = pass. Bike "lifted" by gap tool = failSee More