JonnyHK 

I was just dismantling the bike so it could go in the box for its big aeroplane flight, and I noticed something very strange.

The sidewall of the tyre seemed to have been damaged by something, but not a simple cut or mechanical damage, but rather something like a chemical damage.

See here the residue on the tyre and also on the rim...
IMGP0430..jpg
It is almost as if something had melted the tyre.

Strange also that it was on both sides, symmetrically, and it was right by the valve.

When I took the tyre off (was changing to wet weather tyres anyway) to inspect it, there was damage to the inside as well.
IMGP0434..jpg

My only thought is that this could be frost damage. This wheel was re-inflated using a CO2 not long ago.

Anyone ever seen this before?

I'm thinking that the tyre is now unreliable and is junk.

Dolamite02

Great pics, and yes, I think you're right about the frost damage. It looks like the cold may have caused some of the layers to separate. I can't speak to the reliability of the tire, but others should be able.

madpogue 

I wouldn't use that tyre on the road. You could put a dollar bill / pound note / yuan note (sorry; Idunno what's used in HK these days) inside the tyre at those points as a "liner", and use it on a trainer. Tyvek paper works, too, the kind that's used for package mailing envelopes.

krazygl00

Have you had the bike on a car rack recently? Looks like your wheel may have been heated up by the exhaust. That's just my guess.

Bob Dopolina 

That would be my guess, too.

It may also be a solvent issue.

Frost is nowhere near cold enough to active or facilitate any kind of chemical reaction from any of the chemicals/materials used in tire production. Heat is what you should be thinking about. I used to work with a large German tire maker and I am certain on this point.

Flatballer

Do you use any sort of sealer in the tire? Some sealant's can cause chemical damage to certain tires. Certain manufacturers will void your warranty if you use any sealant in the tire/tube.

This is probably mostly a factor in tubeless, but if you had a hole near there and some sealant got into the tire before sealing the tube....

Yeah, I dunno. As I type this is sounds more and more ridiculous.

Bob Dopolina 

I had a look at your pictures again and I don't understand the damage I am seeing and the fact that your tire casing appears to have been cut where it wraps around the bead by a rim that was wasn't finished well and left too sharp a hook surface (really not uncommon).

what kind of riding had this tire seen before failure?

JonnyHK 

Thanks for the suggestions.

- No car rack (hell, no car at all!)

- Standard tube, no sealant.

- Rim is fine, smooth and hasn't troubled me before (Kinlin 300)

- 'Normal' riding on sealed roads, some wet weather. Nothing my other tyres haven't been through, nothing strange springs to mind.

- Solvents was a thought, but how would I have neatly hit both sides in the same place and not get anywhere else? I've had some cleaning and lubricating products (Simple Green, WD40, Finishline chain lube) on the bike, but these wouldn't be doing this.


The really localised (and symmetrical) damage has me stumped. The frost thought was only because the damage is right by the valve and this wheel is one of the few that I've inflated on the road using CO2.

One side is quite badly damaged where the lower layers are exposed, so I'm putting this baby in the bin.

Bob D - I could cut the damaged section out and post it to you if it might help a diagnosis...

mvnsnd

From the pictures it looks like some kind of solvent got trapped at the interface between the tire and the rim. I don't see the damage beyond that. Plus it looks like the tire was melted for lack of a better term where it came in contact with the rim.

Just a thought, was it parked where an animal could have tried to pee on the wheel? The last place for the pee to evaporate would be that interface. If the tire was warm, it may have made the situation worse.

I think if the tire was frozen by the CO2, it would just crack, not adhere to the rim. Plus I think the tube would insulate the tire some.

chaadster

Looks like run-o'-the-mill "snake bite" to me (i.e. pinch damage).

Flatballer

wtf? Are you high? Your snake bite flats regularly melt your tires to the rim?

spry

Why do you hate people getting a buzz on Friday night?

Flatballer

Friends don't let friends post high.

Bob Dopolina 

If you feel like it sure but I don't work with these companies anymore so I'm not sure how I can help you.

I've been thinking about the CO2 and I am wondering if it may have frozen the tire to the rim and then, as you rode, you ripped the bead loose and damaged the tire. Sort of like getting your tongue stuck on a stop sign (not that you would have experienced this in HK).

What is the consistency of the material still stuck to the rim? Does it seem overly goey? Or is it about the same consistency as the compounds on the tire?

The reason I am thinking solvent is that some kind of catalyst is required to alter the compounds used in tire manufacturing. Solvents can do this. Could you have ridden through something and then hung your bike up? The wheels would settle valve down and anything on the rims would find its' way to the bottom of the wheel and a reaction could occur over time?

Just thinking out loud here...

cycle17

Interesting thinking Bob. Your theory on the solvent and then hanging the bike up is a good one... enjoyed reading that...can tell you're a pretty smart guy. :-)

Shimagnolo

Hey!
Some of those snakes have really powerful venom!

Bob Dopolina 

Pshaw!

chaadster

I might be: '06 Olim Bauda Barbera d'Asti Superiore "Le Rocchette" (old vine, baby!) three-quarters gone!

Anyway, I'll bet you dollars to doughnuts that's snake bite...look up the characteristics...see the diagonal cord impressions? Classic. And the sidewall material is being left on rim after a hard impact is fairly common, too.

And no, my snake bites don't look like that, but only because I don't get pinch damage; I maintain proper inflation, ride with diaphanous refinement, and am a lucky-as-hell mofo to boot.

chaadster

Yeah, it was the venom. Proof:



Okay, seriously...sheldon brown strikes again:

https://www.sheldonbrown.com/brandt/snakebites.html

Bob Dopolina 

I'll take your dollars.

Not a snakebite.

Snakebite doesn't explain the loss of material on the inside of the casing. There may have been an issue when calandering the casing, though. Or there could have been foreign material in the mold or even trapped air when the tire was cooked but that kind of damage is not from a snake bite.

Material being stuck to the rim AND the rimstrip as a result of snakebite? That would be a first for me.

Snakebites leave telltale signs on the tube not the tire.

The chamfer strip is split but this usually happens during installation where the edge of the rim is too sharp from machining the braking surface and it cuts the section of tire as it is dragged onto the rim under tension (due to being the last bit of tire to be put on). Since this split is at the valve it is highly unlikely that that bit of tire was the last to go on.

PM me and I will send you my bank information for deposit.

chaadster

Hmm, obviously you didn't read the link I posted from sheldonbrown.com regarding identification of snake bite/pinch damage. You should.

I don't see how the bit of casing on the rimstrip is germane to the diagnosis; the casing material on the rimstrip can only have fallen there no matter what happened.

Oh...and I prefer cake style to yeast.

Bob Dopolina 

Sorry, I'm not working off second hand information from a website.

I'm basing my opinions on 25 years in the bicycle industry including several years working with tire manufacturers both here and in Germany. At the last company I worked for part of my job was handling warranty claims and factory problems for several manufacturers including a tire company. The only time I've seen damage like this heat (like from a car exhaust as was mentioned) or chemicals were involved.

Casing damage in the inside of the tire such as is the case here and material stuck to the rim strip underneath where the tube would be are not typical of a pinch flat. I don't care what you google.

I can except US Dollars or New Taiwan Dollars.

chaadster

I don't think casing material is stuck to the rim strip; how could that happen?

Anyway, I find it amusing that above, in post #7 you say you don't understand the damage you're seeing, but now, after your hot tire theory was shot down, and the solvent issue, well, dissolved, you are absolutely certain that symmetrical damage clearly showing sidewall contact with the rim and distortion of the inside casing, again symmetrical, is not pinch damage.

Really...that expression "can't see the forest for the trees" expression seems apt here, particularly in light of a plausible alternative explanation.

Oh...and hold the sprinkles.

Bob Dopolina 

Uh...I'm not sure what thread you are reading but it certainly isn't this one.

No-one has "shot down" any of the possible causes I put forth. Heat was first (and not suggested by me) and the OP said no car exhuast was involved. I suggest heat may have been present but that a solvent acted as a catalyst (that would be where the heat came from for those who can't figure it out).

I still think that the damage is chemical in nature either from an external source after manufacturing or as a contaminant during manufacturing. That's why I asked about the consistency of the material on the rim. I think this was some kind of breakdown in the materials in the compound. Anyone who knows a bit about compounding, and who has seen examples of when it goes wrong, would be asking the same questions.

If you read the OP he was dismantling his bike to pack it for a flight. He doesn't mention a flat tire anywhere. Strange, non?

I think JohnnyHK is experienced enough to know if he pinch flat or not. Perhaps if he were to chime in on the condition of his tube it could shed some light on this product failure.

As for the back and forth between us it reminds me of why I stopped posting in this forum and will stop again.

JohnnyHK, I'm pretty sure this damage wasn't caused by a simple pinch flat (esp since yu don't mention a flat tire!). It seems chemical in nature but without feeling the compound on the rim and having the tire in my hands I really can't say for certain. Even if I did have the tire I couldn't say with any certainty when the cause of the damage actually occurred. I am leaning toward contamination during the manufacturing process based on the calandering issue but that's pretty much as far as I can take it with what information I have.

If the tire is fairly new I'd apply for a warranty. You have a case.

kbbpll

You cleaned your chain and over-did it, it ran down the wheel and collected there, and it then proceeded to clean your tire real good. I'm no expert, but solvents are meant to dissolve stuff, right? Did I hear you say WD-40?

Oh well, it's a theory.