TAICHUNG, Taiwan (BRAIN) — Anyone who has had to cut a tire off a rim with a knife, take heart: Bike tire makers have finally had enough too.
Tire makers Challenge, Continental, Mavic, Schwalbe and others met with the World Federation of the Sporting Goods Industry at Bike Week here this week to kick off a discussion about establishing meaningful standards for the way a tire and rim interface. Josh Deetz of Felloe is drafting a set of measurements he thinks will better define the tire-rim interface and then the group plans to come together, with interested rim and wheel makers, to discuss dimensions — maybe during the Taipei Cycle Show next spring.
The current tire and rim standard, ETRTO, does not specify a tire bead shape or size, nor a tolerance for tire bead stretch. And ETRTO does not specify the shape of the rim bead hook, the height of the sidewall or other dimensions tire makers say are critical to tire safety. Nor does ETRTO define what "Tubeless" and "Tubeless-Ready" mean.
"Until a few years ago road rims were 13 millimeters bead-to-bead. Then they grew a few millimeters and now they are all over the place. Take a 23-millimeter-wide road tire and put it on a wide rim and you can expect problems," said Alex Brauns, Challenge Tire's president. "Run that tire tubeless and it burps, or you cannot get the tire off the rim to repair it, who do people blame? They blame tire makers. But the problem is there are no meaningful tire and rim standards to get us out of this mess."
More than anything else it is tubeless road tires and rims that brought tire makers together for this unusual show of solidarity.
"In the motorcycle and auto industries they have specific rim-tire interface standards. Each rim width has an allowable range of tires that will fit. But in bikes people expect to mount a 3-inch-wide 29er tire to any 700c rim because they are both 700c, but that's crazy," Brauns said.
