There are ETRTO standards for rims but not tires. So it’s an issue, unfortunately, as Dan saw first-hand: They shared the results with us, and we were shocked to see a huge variability in both tire bead diameter and stiffness. We’ll share data as we get it, but take our word for now that tires are far from created equal. https://www.slowtwitch.com/...e_Test_Lab_7532.html
Why wouldn’t a company make note for the safety of their customers? Zipp also encourages confirming compatibility: https://sram.zendesk.com/...t-disc-brake-wheels-
But wait…what about the “homogenization” with ETRTO and ISO 5775 that is supposed to happen, which addresses BOTH? Last we heard in the middle of 2019 was that the ISO 5775 was ready to be released soon, but then there was some last minute proposals (led by Stan’s) that was trying to get a “B” standard adopted…
…and then all of the sudden at the beginning of this year, ETRTO unilaterally pushes out an update. Not sure what to make of all of that…except, that when bead hooks are present, there’s less likelihood of tire blowoff, even without the 621.95mm+/-0.5mm specification of the newest ETRTO standard.