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Tire sidewall cracks. Should I worry?

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Tire sidewall cracks. Should I worry?

Old 07-23-16, 04:42 PM
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Tire sidewall cracks. Should I worry?


Are these crack bad? The tires hold air pressure just fine. I will be using them to ride around town 10 to 15 miles few times a week. I don't know how old the tires are.

Should I worry about these tires? Are they safe to ride?

Thanks in advanced.

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Old 07-23-16, 04:54 PM
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I can't really see the severity of the cracks, but eventually, a crack will separate enough so that a portion of the tube will poke through it. Then, when you hit just the right little bump, the tire will pinch the protruding tube, air will scrrrrrream out of it, and your tire will go instantly flat.

Yes, the tube is holding air, but a large enough crack in the tire will destroy a perfectly good tube in a minute. I say have it checked at your local bike shop to see if you have entered the danger zone with these tires yet.
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Old 07-23-16, 06:15 PM
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I would not be concerned about superficial cracks like that; the strength of the tire is in the fabric plies, not the rubber covering them.
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Old 07-23-16, 06:31 PM
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Should the tires get worst you can replace them at that time.
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Old 07-23-16, 06:54 PM
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recently rode almost 50 miles on these & they were fine with a littler glue. your cords aren't showing, you should be fine. if they were 30 yrs old, then that dry rot and age would justify changing them. you can always go with 80-90 lbs instead of 100

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Old 07-23-16, 09:21 PM
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If the cracks extend deep enough to expose the casing you have a potential problem: exposed casing will tend to degrade and eventually allow the inner tube to extrude and burst. Keep an eye on the tire; if it starts to swell, the casing is shot and will fail.
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Old 07-24-16, 02:10 AM
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Those little cracks are called crazing...it occurs as the outside environment, most notably the sun's UV energy, break down the chemical composition of the carcass's outermost layer. The tires are most likely fine to ride on; the only crazing that has ever been a problem for me was the 10+ year old tires on a two axle, 12ft trailer which sat in the sun most of its life. Said crazed tires blew out on a stretch of I-15 near Mesquite, NV after about 300 miles of towing over 4000 lbs.
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Old 07-24-16, 03:33 AM
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The problem is when the tyre fabric, that holds it's shape gets damaged. Sometimes, there are little bulges that come out on sides, like a tyre had swallowed some small ball.

However, if riding on wet, rainy days, water can get through cracked rubber and damage the canvas holding tyre's shape and strength. Then, the tyre can just go boom instantly, without warning.

I rode tyres looking a lot worse than yours. I'd just make sure the front tyre is decent, without cracks, while I'd risk it with the rear.
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Old 07-24-16, 04:42 AM
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I ride in hilly country and I would not risk dodgy tires. If I have any doubts I change them.
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Old 07-24-16, 06:30 AM
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Originally Posted by Ball Bearing
I ride in hilly country and I would not risk dodgy tires. If I have any doubts I change them.
I can tell you for sure that those tires are NOT going to get better by themselves. Trying to squeeze the last few miles out of a worn out part isn't worth it to me. You know you are going to have to replace those tires sooner or later. If you are worried enough those tires to post it here, why put up with that anxiety every time that you ride for an extra month or so before you ultimately replace them?
My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.
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