Tire Bead Jumped the Rim: Still Safe to Use?
06-06-12, 07:06 PM
#1
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Thread Starter
Tire Bead Jumped the Rim: Still Safe to Use?
I had a non-folding Nashbar kevlar tire rated for 110psi pumped up to 120psi and the wire bead jumped the rim in one place. (I went that high because I was touring and had a heavy load–yes, I've learned my lesson). No blowout, thankfully, and I had a spare gatorskin that I put on as soon as I heard the tire rubbing on the brakes. I want to know whether the old tire would still be fine to use at the correct pressure on an unloaded bike, or is the bead completely unusable now? The rubber around the wire bead has been slightly rubbed off, but the wire seems to be completely intact.
06-06-12, 08:11 PM
#2
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120 vs. 110 is too close for the pressure to be a decisive factor blowing the tire off the rim. Odds are that it wasn't seated correctly in the first place.
Or you're using straight sided rims. Kevlar beads absolutely demand hook edge rims for the tires to at max rated pressure.
If you do have straight side rims, you probably can't change them that easily, so I'd replace the tires with wider section tires that will properly handle the load at lower pressures (read here). and stick to steel bead tires which are more suited to straight side rims. Unfortunately, with hook edge rims so predominant these days, it's harder to get good quality tires designed for straight side rims, and in any case, most tire specs. aren't clear about hook vs straight rims.
The advice for a wider tire stands regardless of rim or bead type, anytime you feel justified in over-inflating a tire, consider it a sign that it's too narrow.
Or you're using straight sided rims. Kevlar beads absolutely demand hook edge rims for the tires to at max rated pressure.
If you do have straight side rims, you probably can't change them that easily, so I'd replace the tires with wider section tires that will properly handle the load at lower pressures (read here). and stick to steel bead tires which are more suited to straight side rims. Unfortunately, with hook edge rims so predominant these days, it's harder to get good quality tires designed for straight side rims, and in any case, most tire specs. aren't clear about hook vs straight rims.
The advice for a wider tire stands regardless of rim or bead type, anytime you feel justified in over-inflating a tire, consider it a sign that it's too narrow.
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Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
08-02-12, 02:25 PM
#3
Full Member
Thread Starter
Thanks. I don't think they're straight-sided rims, but I'll double-check. And yes, I've already moved to much wider tires!
Question still stands about the tire that jumped, though: is it safe to re-use (on a lighter loaded bike, of course), or is it a goner?
Question still stands about the tire that jumped, though: is it safe to re-use (on a lighter loaded bike, of course), or is it a goner?
08-02-12, 02:28 PM
#4
Banned
tape over the bead still OK?.. research why it popped off.
poor installation, or the rim tape in the way?
poor installation, or the rim tape in the way?
