why do the folding tires seem to stop at about 37c and tires larger than 37/38 are a wire bead? Does the larger size have a problem of rolling off the rim in a folding tire? I guess 37/38 would work, but it looks like I have the clearance clarence to go bigger.

My guess is the tire mfg's must figure that once you get up to the added weight of a larger tire as compared to a narrower one, the slight weight savings of a kevlar bead won't make enough difference to justify the cost.(?)

My guess is the tire mfg's must figure that once you get up to the added weight of a larger tire as compared to a narrower one, the slight weight savings of a kevlar bead won't make enough difference to justify the cost.(?)

you can get mtb tires much larger than 37 in a kevlar bead so i'm not sure that's the answer. i didn't know you couldn't get larger tires in a kevlar bead, so it's all news to me...

I was searching for some of the bigger tires at places like webcyclery et al. The website says that the larger sizes >37\38 are wire bead and to call for availability.

I've got Ritchey 38's Mountcross in kevlar, and a 42c Zed in kevlar. I know that Maxxis makes the wormdrive in a 42c in kevlar, and you can get several 29" tires in kevlar beads(not that we're talking 29"ers here, but still)

you can get mtb tires much larger than 37 in a kevlar bead so i'm not sure that's the answer.

It's true that most MTB tires are wider than 37c CX tires, and the narrower MTB tires have kevlar or wire usually, whereas most of the widest MTB tires are wire bead only. As a tire gets wider/heavier, the benefit of lighter beads becomes less.

Ever see a kevlar-bead downhill meat? I haven't. And it's not because steel is stronger than kevlar for DH use, because kevlar is plenty strong for a bike tire application.

the 'average consumer' looking for large 700 tires (37 and over) is a recreational rider not a cross racer so the companies are making tires for that demograph (price/durability over weight/perf.). Riders needing HiPerf. low weight 700x38's (us) are few and far between so the industry has no incentive to serve us. look for some 29er MTB treads.