Originally Posted by CdCf
Unhooked rims?
Forgive me, I know very little bicycle terminology...
http://www.yellowjersey.org/photosfr...t/WEINRIMS.JPG
All rim profiles marked "Not suitable for kevlar bead" are unhooked.
For example, look at the bottom two rims. the 210 Sport model is unhooked. That is, the outer edge of the rim wall has no bump(or "hook"), which helps secure the bead on a tire. The higer the pressure of the tire, the more risk there is of the bead sliding off the edge of the rim, allowing the inner tube to rupture. Interesingly, this can lead to "mystery blow-outs", since once the inner tube blows, there's no longer any pressure on the tire, and it pops back into place, good as new, with the inner tube underneath mysteriously popped with a gaping hole.
Below it, model A-125 Sprint has a inward facing hook, which the tire bead butts against as the tire is inflated.
Ignore the two center rim profiles. The 293 racing and Carrera rims are for tubular tires which are glued on.
Bull.There are rims that have a lower presure rating than some hi pressure clinchers.
Any links?
AFAIK, the only rims that had this kind of rated limit were some plastic BMX mags.