# Continental GP4000 4 Season Sidewall Failure



## BruiserBob (Apr 13, 2005)

*Continental Grand Prix 4 Season Sidewall Failure*









Almost killed descending Grimselpass due to catastrophic sidewall failure. Google search shows so many accounts of others having similar issues. Please check sidewall for threads unraveling. I spent the night in the hospital in Interlaken with a concussion and torn shoulder ligaments. 

Never will I put a Continental tire again on my bicycle. I feel lucky to be alive since my Garmin showed I was descending at 54km/h when it blew. I don't want my wife to be a widower because of terrible quality at Continental.


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## Migen21 (Oct 28, 2014)

Is it a gran prix 4 season (which is what it looks like) or a 4000s or 4000s II ?

Most of the accounts I've seen of sidewall failures for Continental tires have been on the original 4000s tire. I don't see many, if any for the 4 Seasons. 

I've been running gran prix four seasons on all of my bikes. Probably 10k miles on them across 4 sets (25mm and 28mm). The sidewalls all look as good as new. I get about 4k miles on the rear tread before I move it to the front.

Is is possible your brake was rubbing the tire? or your rim overheated or something?


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## BruiserBob (Apr 13, 2005)

Fixed the title, yes Grand Prix 4 Season. No brake pad alignment issues, perfectly on the track. Those tires are death traps. I feel lucky to be alive. Was going 51km/h when the sidewall failed.


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## Migen21 (Oct 28, 2014)

Would you mind linking other instances of this happening with this tire? PM if you prefer? I've been riding this tire for a couple of years under the impression that they are safe and reliable. I'm keenly interested to know that this isn't the case.

I haven't had so much as a flat tire on mine in over 2 years of riding them year round, some if it on crappy roads in crappy pacific northwest weather.

Edit: LOL the *only* instances I found doing a google search for "Grand Prix 4 Seasons Sidewall" were YOUR posts on other forums (slowtwitch). Everything else was for the 4000S tire.

I guess my point is, tires can fail for lots of reasons. There could have been a cut earlier in your ride, or you hit something on your fast decent and didn't realize it. Even an occasional manufacturing defect can occur.

I don't really see condemning the entire stock of these tires, or even all Continental tires, as death traps. From what I can see looking online, they seem to be safe and reliable.


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## upstateSC-rider (Aug 21, 2004)

Search the Wheels/Tires sub-forum, Conti sidewall issues are not new, although I don't remember seeing any in quite some time.


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## BruiserBob (Apr 13, 2005)

Migen21, you send me the money for shipping from Zurich Switzerland, I'll post my rear tire to you gratis. Find a nice 11% descent and try it for yourself.


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## PBL450 (Apr 12, 2014)

BruiserBob said:


> Migen21, you send me the money for shipping from Zurich Switzerland, I'll post my rear tire to you gratis. Find a nice 11% descent and try it for yourself.


Migen's point is good and valid one. I understand being upset and injured, this is cycling, sh*t happens. If it's a common problem with the model why not offer him, and all of us, links that help substantiate that as opposed to a snarky reply that just makes you like a shill.


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## bigbill (Feb 15, 2005)

The picture shows a wear line leading to the ripped sidewall. It looks like a few MTB tires I wrecked in my early days due to misaligned brake pad. I've had a couple of sidewall failures a few years ago on GP4K's but it wasn't a ripped sidewall, it was a small section that failed along the direction of the casing which is angled to the rim, not parallel.


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## BikeLayne (Apr 4, 2014)

I had a GP4000SII that I bought at REI rip apart on me. I bought the tire, inflated it to 80psi for the front and the next morning the tire had ripped similar to the one here. Not one mile of cycling on the tire. Luckily I was able to catch a refund at REI. I moved on to Michelin Pro 4 endurance after that which has been a very good tire.


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## Oxtox (Aug 16, 2006)

sorry to hear about the injuries.

tires, like all mass-produced items, are bound to have some small percentage of defects that still pass QC checks.

assuming it's allowable under Swiss law, you could try suing Continental for medical costs and/or pain/suffering.


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## Migen21 (Oct 28, 2014)

|


BruiserBob said:


> Migen21, you send me the money for shipping from Zurich Switzerland, I'll post my rear tire to you gratis. Find a nice 11% descent and try it for yourself.


Yes, actually, I'm going to take you up on this.

PM me your paypal address and what you need for compensation for the shipping of the tire to the west coast of the US (98021 zip code). I'll even throw in a little extra to cover your time and materials.

In the mean time, could we trouble you for a picture of the rest of the tire, or at least one that shows more of that side of the tire?

It's important to know if this is a one time problem for this tire, or if there really are safety concerns with the _*ALL Gran Prix 4 Seasons tires*_. 

If there are, this is the first I've heard of them. Everything I've read about Continental side wall failures has been related to the older model Gran Prix 4000 S, which I don't use. 

I really need to know if I should be pulling these 4 seasons off of my bikes, and if I do, what tire can I replace it with that is similarly durable, and_* has never had a sidewall failure*_?


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## mtrac (Sep 23, 2013)

I had a sidewall fail on a rear, 25mm 4-Season. Fortunately, there was more annoyance than drama. It had 3500 miles on it, was obviously worn, and I shouldn't have tried to nurse it along. I replaced the tires with lesser Grand Prixes; the rear got a small sidewall tear pretty quickly and the front and rear both started flatting at 1700 miles. Replaced with Hutchinson Intensive. After they wear I'm likely going back to 4-Seasons. Notwithstanding the occasional defect another poster noted, you get what you pay for with 4-Seasons.


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## cobra_kai (Jul 22, 2014)

If nothing else this thread made me double check my brake pad positioning.


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## PBL450 (Apr 12, 2014)

Great price! If you trust 'em! 

https://www.biketiresdirect.com/pro...ail&utm_term=0_bcabc9a71b-c1af2c74c8-72522453


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## Pirx (Aug 9, 2009)

BruiserBob said:


> Those tires are death traps. I feel lucky to be alive. Was going 51km/h when the sidewall failed.


You're being overly dramatic. 51km/h (about 32mph) isn't all that fast. A tire blowout doesn't necessarily mean you're crashing. Even if you do, chances are you'll get some good road rash but will be fine otherwise. Sorry to hear to fared a lot worse, though.


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## wim (Feb 28, 2005)

Looks like a section of sidewall separated from the bead. Chances are pretty good that this is a manufacturing defect unless the tire was stressed excessively in that section. Was the tire difficult to mount?


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## Bee-an-key (May 5, 2007)

Yes the older ones had a reputation but from what I saw it was the threads breaking out. You could monitor it and it was mostly cosmetic vs. full blow outs. What happened to you sucks, sorry to hear it but there are thousands of loyal Conti users that have never had problems. See what Conti says and switch to whatever is makes you comfortable. Good luck.


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## wim (Feb 28, 2005)

Bee-an-key said:


> Yes the older ones had a reputation but from what I saw it was the threads breaking out. You could monitor it and it was mostly cosmetic vs. full blow outs.


This doesn't look like the typical Conti sidewall issue of fine carcass threads (the "TPI" stuff) breaking. Apparently, a section of bead or stranded kevlar bead core ripped away from the sidewall instantaneously. No monitoring this.


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## Migen21 (Oct 28, 2014)

The tire in the first post is not the GP 4000S that typically suffered from he sidewall failures. The OP titled the thread incorrectly, and I think it's causing folks to associate those problems with his issue. 

The tire pictured is a Gran Prix 4 Season 320 TPI tire This tire has not had a history of issues like the GP 4000 has.

Just based on the picture, it looks like that tire was cut. Perhaps by brake rub, or perhaps by something in the road. I don't see frayed threads or any kind of thin area that might indicate a manufacturing defect.


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## RHankey (Sep 7, 2007)

Migen21 said:


> Just based on the picture, it looks like that tire was cut. Perhaps by brake rub, or perhaps by something in the road. I don't see frayed threads or any kind of thin area that might indicate a manufacturing defect.


Not sure how you can say it was caused by brake rub, as the 'cut' sidewall appears to have come from well below edge of the rim. Looks like it separated from the bead to me.

I notice the tire was mounted to a CF rim with CF braking surface. Given I gather this occurred during a long downhill decent, I wonder if the tire got overheated from too much braking. Just pure speculation on my part, but CF rims don't dissipate braking heat as well as AL rims.


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## OldZaskar (Jul 1, 2009)

Maybe it's wishful thinking - because I have a new set of these on my bike - but the line leading to the failure, and the failure... are right where I'd expect to see a tire fail from a misaligned pad. But, at the same time, it does look to be in line with the bead... Could you post a couple more pics:
- Another like the one you posted... maybe a bit better lit ;-)
- From the inside of the tire at the failure
- From the inside; adjacent to the failure


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## Migen21 (Oct 28, 2014)

My statement was not definitive. My observation is the same as yours, based on the picture

Sent from my LG-H830 using Tapatalk


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## GKSki (Nov 12, 2014)

One thing I wondered about in this thread is putting 4K on a rear tire and then rotating it to the front. No way I would ever go that direction. Maybe front to back but preferably not. Good luck cornering well on a tire that has seen 4K of wear from the back wheel. Sometimes tires just have to be disposed of or relegated to the rollers.


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## bradkay (Nov 5, 2013)

Pirx said:


> You're being overly dramatic. 51km/h (about 32mph) isn't all that fast. A tire blowout doesn't necessarily mean you're crashing. Even if you do, chances are you'll get some good road rash but will be fine otherwise. Sorry to hear to fared a lot worse, though.


Years ago I had a rear wheel lockup at 45mph and never even came close to going down. It did skid right through a brand new tire, however... The lockup came from a drawstring on a stuff sack strapped under the saddle - the drawstring came loose and snagged on the presta valve.


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## factory feel (Nov 27, 2009)

operator error.


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## duriel (Oct 10, 2013)

That blowout area does look like it has been cut, where are all the cords that are to be connected to the bead?
There must have been (or not have been) a thousand strands of cord broke or cut for that lenght.

I'm going to speculate that this tire failed due to 1 of 3 reasons. 
1. tire was rode flat, the cords were damaged by the CF wheel, subsequently failed when a new tube was installed.
2. something got caught in the chain or seat stay that later fell out that cut the sidewall as the tire rotated.
3. hmmm.


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## Fajita Dave (Dec 1, 2015)

That is a pretty clean cut right through the cords. The cords cross so I can't imagine how a defect could fail in such a clean cut along the exact arch of the rim. I wonder what the tube looks like.

In the lighter photo OldZaskar posted you can clearly see the sidewall damage goes beyond the cut section.


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## OldZaskar (Jul 1, 2009)

GKSki said:


> One thing I wondered about in this thread is putting 4K on a rear tire and then rotating it to the front. No way I would ever go that direction. Maybe front to back but preferably not. Good luck cornering well on a tire that has seen 4K of wear from the back wheel. Sometimes tires just have to be disposed of or relegated to the rollers.


Pssst... the tire doesn't have 4,000 miles on it - it's a GP4000


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## GKSki (Nov 12, 2014)

Not a Conti user, except for Sprinters. Is that a Conti joke? He did say he puts 4k miles on the rear then moves it to the front. Wouldn't want to be in a paceline with him.


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## den bakker (Nov 13, 2004)

GKSki said:


> Not a Conti user, except for Sprinters. Is that a Conti joke? He did say he puts 4k miles on the rear then moves it to the front. Wouldn't want to be in a paceline with him.


it might help if you put the reply under the right post and/or quote the post.


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## willstylez (Sep 15, 2011)

I've been riding GP 4 Seasons for the past 3 years, and rarely get flats....let alone any sidewall tearing. This particular tire has about 3/4 of the miles than that of the OP's, and it's still in fairly good condition, even with NYC riding. I'll be keeping a close eye on the sidewall threads, just to be safe.

And yes, when worn out, I'll rotate the front tire to the rear.....


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## ericm979 (Jun 26, 2005)

I have had this type of failure where the bead separates from the tire, and seen it with a team mate's wheel. Both cases were on steep descents, Michelin tires and carbon clinchers. I think that two factors may contribute- excess heat from carbon clinchers and damaging the bead by sliding the tire iron under it during installation/removal.

Carbon fiber does not conduct heat well, so braking heat stays localized in the rim walls. The bead is the part of the tire in contact with that rim wall so it gets hot too. Modern CF rims can handle more heat without softening but that heat is still there getting the tire bead hot.

Many people when removing a tire will get some of the bead over the rim and then slide a tire level between the rim and tire to quickly remove the tire. I used to do that until the above failure.

I don't know if you need both factors (I had on my failure) or just bead heat is enough to cause the failure. I stopped using Michelins and am more careful with my tire levers.


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## bradkay (Nov 5, 2013)

I wonder if overheating rims caused the glue which holds the bead on to fail?


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## aclinjury (Sep 12, 2011)

Conti 4000 and 4000S have issues with sidewall, and I'm reading that their new 4000II is still having the same issue. Not sure about the 4-season, but wouldn't suprise me if they do.

But your issue could have been heat related too since you're on carbon rim. Hard to tell just by looking at the pic.


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## AndreyT (Dec 1, 2011)

bradkay said:


> ... the glue which holds the bead on ...


What exactly are you referring to?


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## woodys737 (Dec 31, 2005)

duriel said:


> That blowout area does look like it has been cut, where are all the cords that are to be connected to the bead?
> There must have been (or not have been) a thousand strands of cord broke or cut for that lenght.
> 
> I'm going to speculate that this tire failed due to 1 of 3 reasons.
> ...


4. It's a counterfeit.


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## GKSki (Nov 12, 2014)

willstylez said:


> I've been riding GP 4 Seasons for the past 3 years, and rarely get flats....let alone any sidewall tearing. This particular tire has about 3/4 of the miles than that of the OP's, and it's still in fairly good condition, even with NYC riding. I'll be keeping a close eye on the sidewall threads, just to be safe.
> 
> And yes, when worn out, I'll rotate the front tire to the rear.....


O.K. then. But who rotates a used rear tire to the front? Death wish?


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## wim (Feb 28, 2005)

AndreyT said:


> What exactly are you referring to?


While the bead is not a separate hoop held on with glue to the sidewall, the question is legitimate. The sidewall material wraps around the core strands (kevlar in this case) and is glued to itself as the wrap comes back around. The glue between the sidewall layers just above the core pocket can soften with heat, possibly allowing delamination and subsequent ripping.


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## duriel (Oct 10, 2013)

I don't think you would call it glue. It is basically rubber on the inside volcanized to the rubber on the outside, after it loops the bead. But if this volcanizing fails the bead would be clearly visible without any rubber on it, as the cords are not tore but just lost hold of the inside of the outside tire wall and let go..


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## mapeiboy (Oct 31, 2007)

I have been using cont GP 4000s for the last 7 years without any sidewall issue at all . I really don't know why people have so many sidewall problems from this tire . My suggestion is to check your tires after each ride .


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## ericm979 (Jun 26, 2005)

I've had one sidewall cut (after riding a ways on gravel) in the last five years that I have been using GP4000s. They get fewer flats than the Michelins and Panaracers I used before.


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## den bakker (Nov 13, 2004)

mapeiboy said:


> I have been using cont GP 4000s for the last 7 years without any sidewall issue at all . I really don't know why people have so many sidewall problems from this tire . My suggestion is to check your tires after each ride .


really depends one how much crap is on the road. In any case the sidewall breaches typically are very different than what the OP is showing.


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## mfdemicco (Nov 8, 2002)

A sharp edge on the rim can cause a cut sidewall just above the bead. Worth checking for that.


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## PBL450 (Apr 12, 2014)

woodys737 said:


> 4. It's a counterfeit.


Wheel? Tire? Both?


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## wim (Feb 28, 2005)

duriel said:


> I don't think you would call it glue. It is basically rubber on the inside volcanized to the rubber on the outside, after it loops the bead.


You're right, "glued to itself / the glue" is not right. Perhaps "bonded to itself / the bond" would have made things a little clearer.


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## RHankey (Sep 7, 2007)

What's more interesting is the OP has basically come on here to slag Conti with 3 posts, out of a total of 5 posts since 2005, and apparently bashed Conti elsewhere too, yet has only one crappy picture to support his claims. Something sounds suspect here.

I'm speculating excessive rim heat, and improper installations methods compromised the casing where it wraps around the bead. Some Conti/rim combinations can be a really tight fit, making it all the more likely the casing got damaged during install.

Until the OP can provide a couple better photos of the torn tire after removing the tire from the rim, I think all we can do is speculate, and I don't think it fair for the OP to be so quick to be blaming Conti. A couple good photos will make it very clear what happened.


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## PBL450 (Apr 12, 2014)

RHankey said:


> What's more interesting is the OP has basically come on here to slag Conti with 3 posts, out of a total of 5 posts since 2005, and apparently bashed Conti elsewhere too, yet has only one crappy picture to support his claims. Something sounds suspect here.
> 
> I'm speculating excessive rim heat, and improper installations methods compromised the casing where it wraps around the bead. Some Conti/rim combinations can be a really tight fit, making it all the more likely the casing got damaged during install.
> 
> Until the OP can provide a couple better photos of the torn tire after removing the tire from the rim, I think all we can do is speculate, and I don't think it fair for the OP to be so quick to be blaming Conti. A couple good photos will make it very clear what happened.


Thanks. I was waiting for someone, other than me, to bring this up. I already called Mr. One Post Wonder a shill. He is simply part of the 40% of Internet content that is pure shill. Reviews... Shill. Forums... Shill. He's not injured... He's a 20-something from India who's home playing video games. His company got hired, by Michelin, to create a stir about Conti tires. Not a troll. A SHILL. On the upside, he's part of a rapidly growing middle class in India. On the downside, he and his ilk just pepper the Internet with absolute sh*t because that's what their employers are hired to do. He has no moral horse in this race, he's just out getting a Starbucks.


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## GKSki (Nov 12, 2014)

ericm979 said:


> I have had this type of failure where the bead separates from the tire, and seen it with a team mate's wheel. Both cases were on steep descents, Michelin tires and carbon clinchers. I think that two factors may contribute- excess heat from carbon clinchers and damaging the bead by sliding the tire iron under it during installation/removal.
> 
> Carbon fiber does not conduct heat well, so braking heat stays localized in the rim walls. The bead is the part of the tire in contact with that rim wall so it gets hot too. Modern CF rims can handle more heat without softening but that heat is still there getting the tire bead hot.
> 
> ...


So how else are you getting these tight tires off other than that traditional means?


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## Migen21 (Oct 28, 2014)

Looking at this picture closer, if you follow the tear line going forward (away from the viewer) there is a line continuing past the tear. It's hard to say what that tear is, but it looks like either a rub mark, perhaps from a brake pad, or perhaps where the rim got hot and melted into the side of the tire.

I'm more and more convinced that this is not a manufacturing or design defect, but more likely operator error.


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## wim (Feb 28, 2005)

PBL450 said:


> Thanks. I was waiting for someone, other than me, to bring this up. I already called Mr. One Post Wonder a shill.


Yes, should've seen this from the beginning, but I fell for it. The bizarre exaggerations (death because of a bicycle tire blowout, for example) should have tipped me off. I ignored them since making bicycling much more dangerous than it really is seems to be in high fashion right now.


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## BlazingPedals (Apr 4, 2013)

A few weeks ago I had a blowout and subsequent crash. The failure looked similar, but in my case it was caused by the sharp corner on my carbon rim.


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## Oxtox (Aug 16, 2006)

PBL450 said:


> Thanks. I was waiting for someone, other than me, to bring this up. I already called Mr. One Post Wonder a shill.


so, the guy (as a pre-teen in India) signs up 11 years ago and then patiently waits for his 'shill cell' to be activated by the controllers at Michelin...? 

got any other good conspiracy theories to share...?


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## RHankey (Sep 7, 2007)

PBL450 said:


> Thanks. I was waiting for someone, other than me, to bring this up. I already called Mr. One Post Wonder a shill. He is simply part of the 40% of Internet content that is pure shill. Reviews... Shill. Forums... Shill. He's not injured... He's a 20-something from India who's home playing video games. His company got hired, by Michelin, to create a stir about Conti tires. Not a troll. A SHILL. On the upside, he's part of a rapidly growing middle class in India. On the downside, he and his ilk just pepper the Internet with absolute sh*t because that's what their employers are hired to do. He has no moral horse in this race, he's just out getting a Starbucks.


That sounds rather harsh and racist and not much better than the OP. And that was certainly not the point I was trying to make. I'll give the OP the benefit of the doubt that the little info he has provided us is truthful and has no ill-intent. However, unless he has done a whole bunch more digging than what he has provided us, I fear he has almost certainly been way too quick to slag the tire maker when there are any number of other possible causes, most of which would point to pilot error. If he was trying to make a credible case, he hasn't done himself any good by stirring the pot with such inflammatory accusations and then ducking for cover.


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## BruiserBob (Apr 13, 2005)

Für alle Conti ball-washers, Sie sind Arsche. Ich bin glücklich nicht getötet. Aber nicht lang zurück auf des Alpen Velofahren.


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## Migen21 (Oct 28, 2014)

Nice view. Enjoy the ride on your presumably inferior tires....


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## aclinjury (Sep 12, 2011)

BruiserBob said:


> Für alle Conti ball-washers, Sie sind Arsche. Ich bin glücklich nicht getötet. Aber nicht lang zurück auf des Alpen Velofahren.
> 
> View attachment 314080


legit!


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## aclinjury (Sep 12, 2011)

BlazingPedals said:


> A few weeks ago I had a blowout and subsequent crash. The failure looked similar, but in my case it was caused by the sharp corner on my carbon rim.


some cotton tires will have a disclaimer saying it will not allow you to use it on carbon rims. Apparently carbon rims can have sharp edged that will cut into the tire. That's why they say to use a fine sandpaper and lightly sand over the hook region of carbon rims


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## arai_speed (Aug 19, 2003)

BruiserBob said:


> Für alle Conti ball-washers, Sie sind Arsche. Ich bin glücklich nicht getötet. Aber nicht lang zurück auf des Alpen Velofahren.



Translation:


"*ÜR all Conti ball - washers , you are asses . I'm not happy killed . But not long back to the Alps cycling* "


</pre>


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## lebikerboy (Feb 22, 2006)

arai_speed said:


> Translation:
> 
> 
> "*ÜR all Conti ball - washers , you are asses . I'm not happy killed . But not long back to the Alps cycling* "
> ...


Nice mature response...


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## den bakker (Nov 13, 2004)

arai_speed said:


> Translation:
> 
> 
> "*ÜR all Conti ball - washers , you are asses . I'm not happy killed . But not long back to the Alps cycling* "
> ...


I am luckily not killed but won't be back riding in the alpes anytime soon.


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## Jay Strongbow (May 8, 2010)

BruiserBob said:


> Für alle Conti ball-washers, Sie sind Arsche. Ich bin glücklich nicht getötet. Aber nicht lang zurück auf des Alpen Velofahren.
> 
> View attachment 314080


The important question here is how to heck do they plow the roads like that with such precision cutting the snow evenly along the side, and why? Is that in the German alps?


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## tlg (May 11, 2011)

Jay Strongbow said:


> The important question here is how to heck do they plow the roads like that with such precision cutting the snow evenly along the side, and why? Is that in the German alps?


Maybe it wasn't plowed.


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## aejc (Jun 9, 2004)

Here's a Michelin Pro 3 -- I had sidewall issues with two of them. In both instances, the tires had been stored for a while and developed sticky sidewalls. Both seemed ok at Austin, TX elevation. Both failed on mountain descents: one in Colorado, another in Utah. In both instances, it was likely a combination of tire age (the compound of the colored sidewall was not durable -- I had a blue version that had drywall rot), heat (brakes on carbon fiber rim), and pressure (higher altitude). 

The conditions of OP's failure were likely more of a factor than the brand of tire.


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## arai_speed (Aug 19, 2003)

aejc said:


> View attachment 314087
> 
> 
> Here's a Michelin Pro 3 -- I had sidewall issues with two of them. In both instances, the tires had been stored for a while and developed sticky sidewalls. Both seemed ok at Austin, TX elevation. Both failed on mountain descents: one in Colorado, another in Utah. In both instances, it was likely a combination of tire age (the compound of the colored sidewall was not durable -- I had a blue version that had drywall rot), heat (brakes on carbon fiber rim), and pressure (higher altitude).
> ...


Same thing happened to a Michelin Pro 4 I had:










https://forums.roadbikereview.com/wheels-tires/defective-michelin-pro-4-course-353008.html


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## Natedogz (Aug 25, 2010)

Pirx said:


> You're being overly dramatic. 51km/h (about 32mph) isn't all that fast. A tire blowout doesn't necessarily mean you're crashing. Even if you do, chances are you'll get some good road rash but will be fine otherwise. Sorry to hear to fared a lot worse, though.


X2, but still not good...thanks, but no thanks (pause) I'll pass. 



ericm979 said:


> I have had this type of failure where the bead separates from the tire, and seen it with a team mate's wheel. Both cases were on steep descents, Michelin tires and carbon clinchers. I think that two factors may contribute- excess heat from carbon clinchers and damaging the bead by sliding the tire iron under it during installation/removal.
> 
> Carbon fiber does not conduct heat well, so braking heat stays localized in the rim walls. The bead is the part of the tire in contact with that rim wall so it gets hot too. Modern CF rims can handle more heat without softening but that heat is still there getting the tire bead hot.
> 
> ...


This sounds very plausible along with CF rims should have a light sanding on the bead hook area with some 1000 grit sandpaper before initial use.



BruiserBob said:


> Für alle Conti ball-washers, Sie sind Arsche. Ich bin glücklich nicht getötet. Aber nicht lang zurück auf des Alpen Velofahren.


Glad to see you back in the saddle, enjoy the ride.


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## wim (Feb 28, 2005)

BruiserBob said:


> Für alle Conti ball-washers, Sie sind Arsche. Ich bin glücklich nicht getötet. Aber nicht lang zurück auf des Alpen Velofahren.


So where you're from? Obviously, German is very difficult for you.


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## den bakker (Nov 13, 2004)

wim said:


> So where you're from? Obviously, German is very difficult for you.


given it happened at Grimselpass where do you think?


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## wim (Feb 28, 2005)

den bakker said:


> given it happened at Grimselpass where do you think?


I don't know. The German he posted is an atrocious computer translation.


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## mimason (Oct 7, 2006)

He is in Switzerland and what he wrote was Schweiz Deutsch or rather Scheiß Deutsch. Den Bakker translated it best.....but not long back in the Alps bike riding.

I can see how he is pissed off though with the lack of compassion albeit it does appear to be a prior tire wall damage that caused the failure.


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## PBL450 (Apr 12, 2014)

RHankey said:


> That sounds rather harsh and racist and not much better than the OP.


Please, how have I made a racist statement? Please be very specific...


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## wim (Feb 28, 2005)

mimason said:


> He is in Switzerland and what he wrote was Schweiz Deutsch or rather Scheiß Deutsch. Den Bakker translated it best.....but not long back in the Alps bike riding


The German he posted suggests he doesn't speak Swiss German. That's why I wondered where he's from. I know where the Grimsel Pass is and what languages the people speak who live there. Doesn't matter, just idle curiosity.


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## RHankey (Sep 7, 2007)

PBL450 said:


> Please, how have I made a racist statement? Please be very specific...


Umm, go back and re-read what you posted. There was no need to be smearing people from India.


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## PBL450 (Apr 12, 2014)

RHankey said:


> Umm, go back and re-read what you posted. There was no need to be smearing people from India.


Thats not even slightly specific. You go read what I posted. I didn't smear middle class Indians working in call centers in the tech sector one bit. Playing video games might be an age smear. Starbucks might be a middle class smear. Get your isms right or keep your errant self defined politically correct comments to yourself. If you have issue BE SPECIFIC and define your issue. No, "go read it" isn't worth a reply... How is being part of a swelling middle class a slur? Sure, development is distorted in India, but it is one of the most rapidly developing economies in the world. Just read any UNDP report. 

Define how how I smeared people from India?


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## stevedodds (Jan 16, 2002)

I will keep using my Continental tires. Sorry to hear anyone has a problem .  After 50 +years a professional tec and team mechanic, yes any product can have that one in thousand blem, conti one of the best selling tires for good reasons so you might see a few just do to numbers sold. 

In this case I am not so sure that's the case. looks like a couple other possibility to me, brake pad alignment or wrong brake pads , riding with under inflation, rim over heat on a down hill descent at the time of the ride or other combination of rides that heat attacked the tire.

I hate to think or say it could be a case this is the Michelin tire salesman knocking the other guy.

In the end always inspect your bike and tires before the ride. 99 times out of a 100 you will catch a problem before its a problem. And do not ride past your ability, the speed this guy was riding was pro level its just fact pro riders have a accident from time as any one can.

I do hope he heals quick and gets back in the saddle again.

steve


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## velodog (Sep 26, 2007)

GKSki said:


> O.K. then. But who rotates a used rear tire to the front? Death wish?


I would suppose that when the rear is worn out, the front goes to the rear and the new one goes on the front.

That's what I do anyways.


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## Lombard (May 8, 2014)

velodog said:


> I would suppose that when the rear is worn out, the front goes to the rear and the new one goes on the front.
> 
> That's what I do anyways.


Same here.


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## Migen21 (Oct 28, 2014)

I think I mentioned that I rotate my front/rear tires after about 4k miles. Maybe that is what he's taking exception to. The 4k rear tire still has plenty of tread. It's not like it's worn to the cords or something. Rear tires wear faster than fronts, so rotating them extends the lifespan. It's the same concept as rotating your car tires.


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## aclinjury (Sep 12, 2011)

Some said it could be brake pad rubbing. I'm not convinced at all. There are no marks on the sidewall indicating something has rubbed it. I would think there would be signs of rubber fraying all around the sidewall if something was rubbing it. And the delamination region on the tire looks to be right at or beneath the hook of the rim and doesn't look like an area the brake pad would rub if it were to rub.

I'm more inclined to think a combination of a defective tire and heat from extreme braking. This defect might not have been revealed if it was riding on the flat where heat from braking is much lower.

Also, I've read anecdotal reviews that some Conti tires (amongst other brand tires too) being sold by the big internet sellers (especially the ones from the UK), are B-grade tires and/or tires that have been sitting in the warehouse for a while and now they're liquidating them with huge discounts. The reviews that I read were mostly reviews from buyers who left their feedbacks on those major UK sellers. One reviewer said he bought Vittoria tubular Corsa CX tires that were 2 years old (older model) and was not happy with it. So it would not surprise me if OP got a defective tire that happened to reveal itself a mountain descent, and if OP was riding on the flat, we may have never heard about it.


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## GKSki (Nov 12, 2014)

Migen21 said:


> I think I mentioned that I rotate my front/rear tires after about 4k miles. Maybe that is what he's taking exception to. The 4k rear tire still has plenty of tread. It's not like it's worn to the cords or something. Rear tires wear faster than fronts, so rotating them extends the lifespan. It's the same concept as rotating your car tires.


Taking exception to is a little strong. Just trying to save you some grief. Bicycle tires are not like car tires and the bicycle front tire is immensely more important than the rear for handling and braking. One can probably deal with a rear tire failure, but front tire, not so much.

Better to move your lesser worn front tire to the rear, replace the front with a new tire and retire the worn rear to rollers or discard.


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## Oxtox (Aug 16, 2006)

Migen21 said:


> I think I mentioned that I rotate my front/rear tires after about 4k miles. Maybe that is what he's taking exception to. The 4k rear tire still has plenty of tread. It's not like it's worn to the cords or something. Rear tires wear faster than fronts, so rotating them extends the lifespan. It's the same concept as rotating your car tires.


this SOP is srsly flawed.


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## tka (Jun 11, 2014)

GKSki said:


> Taking exception to is a little strong. Just trying to save you some grief. Bicycle tires are not like car tires and the bicycle front tire is immensely more important than the rear for handling and braking. One can probably deal with a rear tire failure, but front tire, not so much.
> 
> Better to move your lesser worn front tire to the rear, replace the front with a new tire and retire the worn rear to rollers or discard.


I run a new tire for about 250 miles on the rear before I use it on the front, just in case something is wrong with it. Most defects seem to occur in this timeframe. After 250 miles I'll swap the new tire to the front, the front tire to the rear, and the old rear to the trash.


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## arai_speed (Aug 19, 2003)

tka said:


> I run a new tire for about 250 miles on the rear before I use it on the front, just in case something is wrong with it. Most defects seem to occur in this timeframe. After 250 miles I'll swap the new tire to the front, the front tire to the rear, and the old rear to the trash.


When I buy new tires, I take the old ones off (front & rear) and put the new ones on (front & rear). Pump them up, and go for a ride!

#ThrowingCautionToTheWind


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## GKSki (Nov 12, 2014)

Glad CXWrench is not onboard for this.:mad2:


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## PBL450 (Apr 12, 2014)

RHankey said:


> Umm, go back and re-read what you posted. There was no need to be smearing people from India.


I'm still waiting for your explanation? Calling someone a racist is a serious, toxic and aggressive accusation. If you are going to make the accusation you had better be able to substantiate your claim with a reasonable and detailed explanation. If you can't make a reasonable exhalation then have the balls to say that. If you can, then do it, it's 48 hours after my first request. I would NEVER, EVER call someone a racist without being able to explain my poisoned arrow. So?


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## Lombard (May 8, 2014)

PBL450 said:


> I'm still waiting for your explanation? Calling someone a racist is a serious, toxic and aggressive accusation. If you are going to make the accusation you had better be able to substantiate your claim with a reasonable and detailed explanation. If you can't make a reasonable exhalation then have the balls to say that. If you can, then do it, it's 48 hours after my first request. I would NEVER, EVER call someone a racist without being able to explain my poisoned arrow. So?


Racist is a bit of a harsh word, but re-read what you posted:



PBL450 said:


> I already called Mr. One Post Wonder a shill. He is simply part of the 40% of Internet content that is pure shill. Reviews... Shill. Forums... Shill. He's not injured... He's a 20-something from India who's home playing video games.


First off, how do you know he is from India? Feel free to point out if I missed something, but it shows up nowhere else in this thread that the OP is from India. It appears you are making a speculation, which could be perceived as racist, or at least disparaging.


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## Migen21 (Oct 28, 2014)

This is the Internet. Unless someone has changed the rules recently, no one is obligated to defend anything they say. 

It's always been that way, and will probably always be that way...


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## SPlKE (Sep 10, 2007)

Migen21 said:


> This is the Internet. Unless someone has changed the rules recently, no one is obligated to defend anything they say.
> 
> It's always been that way, and will probably always be that way...


Incorrect.


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## Migen21 (Oct 28, 2014)

Please defend your position with facts (made up or otherwise), photoshopped pictures, misquoted citations taken out of context and some general assumptions for good measure!


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## ROAD&DIRT (Mar 27, 2009)

Pirx said:


> You're being overly dramatic. 51km/h (about 32mph) isn't all that fast. A tire blowout doesn't necessarily mean you're crashing. Even if you do, chances are you'll get some good road rash but will be fine otherwise. Sorry to hear to fared a lot worse, though.



^^ This 

I have had a double blowout going down hill and around a bend over 40mph and kept the bike upright, Did I get mad and quickly called my tire faulty and posted how dangerous the tires are and a threat to everybody... no! 

It's biking and sh_t happens.

However on the sympatric side, I am sorry you experienced what you did and do hope for full speedy recovery...


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## SPlKE (Sep 10, 2007)

Migen21 said:


> Please defend your position with facts (made up or otherwise), photoshopped pictures, misquoted citations taken out of context and some general assumptions for good measure!


Let us let Alfred Einstein's wisdom guide us:

"Without facts, the universe is but a confounded chaotic composite of meaningless matter and effusive energy."

-- Alfred Einstein (in a letter to his colleague Neil Bore)


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## Lombard (May 8, 2014)

SPlKE said:


> Let us let Alfred Einstein's wisdom guide us:
> 
> "Without facts, the universe is but a confounded chaotic composite of meaningless matter and effusive energy."
> 
> -- Alfred Einstein (in a letter to his colleague Neil Bore)


Me thinks you may be getting the two Einsteins mixed up. I'm pretty sure you meant to quote the physicist, not the musicologist.


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## SPlKE (Sep 10, 2007)

Lombard said:


> Me thinks you may be getting the two Einsteins mixed up. I'm pretty sure you meant to quote the physicist, not the musicologist.


Holey crap. You're right. I meant Allen Einstein, the physicist.

The one who discovered that Time = Money. T=M[SUP]2[/SUP] or something like that.


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## Jay Strongbow (May 8, 2010)

PBL450 said:


> Thats not even slightly specific. You go read what I posted. I didn't smear middle class Indians working in call centers in the tech sector one bit. Playing video games might be an age smear. Starbucks might be a middle class smear. Get your isms right or keep your errant self defined politically correct comments to yourself. If you have issue BE SPECIFIC and define your issue. No, "go read it" isn't worth a reply... How is being part of a swelling middle class a slur? Sure, development is distorted in India, but it is one of the most rapidly developing economies in the world. Just read any UNDP report.
> 
> Define how how I smeared people from India?



Did I miss where someone mentioned you said anything about working in call centers in tech? Sounds like you're putting words in your own mouth now.

You certainly did smear Michelin. I'd saying your conspiracy theory is at least as bad a smear on a company (not that anyone is insane enough to take you seriously though) as someone saying they got a flat tire.
Strange stuff you're posting here.


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## Migen21 (Oct 28, 2014)

SPlKE said:


> Let us let Alfred Einstein's wisdom guide us:
> 
> "Without facts, the universe is but a confounded chaotic composite of meaningless matter and effusive energy."
> 
> -- Alfred Einstein (in a letter to his colleague Neil Bore)


When Al_*FRED*_ starts contributing some actual wisdom to these forums, we can start playing by smarter rules...


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## PBL450 (Apr 12, 2014)

Jay Strongbow said:


> (not that anyone is insane enough to take you seriously though)


Good god I hope this is so and no one is insane enough to take that seriously.


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## PBL450 (Apr 12, 2014)

Migen21 said:


> When Al_*FRED*_ starts contributing some actual wisdom to these forums, we can start playing by smarter rules...


Damn... I can't rep that entire exchange...


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## PBL450 (Apr 12, 2014)

Lombard said:


> Racist is a bit of a harsh word, but re-read what you posted:
> 
> 
> 
> First off, how do you know he is from India? Feel free to point out if I missed something, but it shows up nowhere else in this thread that the OP is from India. It appears you are making a speculation, which could be perceived as racist, or at least disparaging.


"Italians make great bicycles" is equally as racist.


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## Tschai (Jun 19, 2003)

PBL450 said:


> "Italians make great bicycles" is equally as racist.


They don't anymore.


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## PBL450 (Apr 12, 2014)

Tschai said:


> They don't anymore.


OK, fair enough... "Italians design great stickers to put on Giant's Tiwanese bicycles."


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## JasonB176 (Aug 18, 2011)

ROAD&DIRT said:


> ^^ This
> 
> I have had a double blowout going down hill and around a bend over 40mph and kept the bike upright, Did I get mad and quickly called my tire faulty and posted how dangerous the tires are and a threat to everybody... no!
> 
> ...


Agreed. I had a tire blowout at 35MPH and kept control of the bike. 32MPH is not remotely fast.

It sucks this happened but I was also surprised at the emphasis on the fact that it occurred on a descent as if a descent is even needed to achieve 32MPH.


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## mfdemicco (Nov 8, 2002)

Anyone else notice that threads come off the chafer strip and get wrapped in the derailleur pulleys and freehub? This is on the 4000S though and might not apply to the 4 Seasons. 


Sent from my iPhone using Tapatalk


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## Lombard (May 8, 2014)

PBL450 said:


> "Italians make great bicycles" is equally as racist.



Do you mean like Chinarellos?  

I guess you could argue that a "racist" remark isn't necessarily a negative one about a group, but one that emphasizes a stereotype.

More to the point of why your remark was perceived as racist was your assumption that the OP was "a 20-something from India who's home playing video games" when there was no basis for this assumption.


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## jlandry (Jan 12, 2007)

Yup. My last 2 pairs did exactly this.



mfdemicco said:


> Anyone else notice that threads come off the chafer strip and get wrapped in the derailleur pulleys and freehub? This is on the 4000S though and might not apply to the 4 Seasons.
> 
> 
> Sent from my iPhone using Tapatalk


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## wim (Feb 28, 2005)

> Anyone else notice that threads come off the chafer strip and get wrapped in the derailleur pulleys and freehub?


I had someone on Conti tires point these wrap-around threads out to me and say "Did you sell me sew-up tires, by any chance?" Couldn't quite figure out what he meant until it became clear that to him, a tire with threads in it was a sew-up tire. 

His belief wasn't so bizarre as it seems. Back in the day when tubular tires were the only option for "serious" riders, unraveling sidewall threads were so common that part of bicycle maintenance was to re-coat your sidewalls once a year or so with a thin layer of rubber cement to keep those threads in place.


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## AndreyT (Dec 1, 2011)

mfdemicco said:


> Anyone else notice that threads come off the chafer strip and get wrapped in the derailleur pulleys and freehub?


When the tire has that strip, then yes, eventually threads begin to unravel and hang around. Although I have never had them reach that far to get into the cogs or RD.

No all tires have that strip though. I wonder what guides the manufacturers decision to use that strip. Is it just to protect the sidewall from the rim edge?


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## truk (Jan 9, 2013)

Definitely scary. Hope you recover well. Thanks for bringing it to our attention, and I'm not here to discount your concerns. I just noted some scary posts, so I wanted to say:

1) These are fairly thin race tires, and my GP4000sII's weigh less than some tubulars. Check all race tires often for cuts and abrasions in broad daylight, not the night before. Check those brake pads. This doesn't look to me to be a maladjustment issue. It's something else. Looks like a defect or cut.
2) Hands are for installing and removing race tires. Tire irons should never be used on fragile race tires or carbon rims. Learn the proper procedure.
3) Tire pressure is critical, too low and you can cut the sidewall when you hit a bump, too high and you may blow the bead. Lately on the advice of media, I've seen a lot of low pressures being used with wider tires. Note that wider tires have a larger exposed sidewall. Use a pressure/weight chart from the manufacturer, and don't run too low a pressure. Also, tubes are designed for air. The cold cycling of CO2 and inflation speed make me nervous with light tubes/tires. Use a lightweight pump unless it's snowing?
4) Race tires should be replaced, not rotated. Hot days are a good excuse. Don't go beyond the wear indicators. Replace the tube when you replace the tire, especially latex. Remove the tire as little as possible. Replace if the bead is stretched.
5) Latex guys, watch the heat, pump your brakes, replace tubes when it's hot. Pay extra attention to your tires in the heat. Switch to butyl on really hot days descending.
6) If you're going to ride race tires, know and watch what you're riding through. Replace them when worn. Otherwise ride Gatorskins and heavy tubes.

Stuff like this happens with all tires, but diligence can reduce it. And thanks again for bringing it to our attention. I just checked my tires again.


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## truk (Jan 9, 2013)

Looks to me like UV deterioration. UV destroys everything. Replace them before they get old.


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## PBL450 (Apr 12, 2014)

Lombard said:


> Do you mean like Chinarellos?
> 
> I guess you could argue that a "racist" remark isn't necessarily a negative one about a group, but one that emphasizes a stereotype.
> 
> More to the point of why your remark was perceived as racist was your assumption that the OP was "a 20-something from India who's home playing video games" when there was no basis for this assumption.


Haha! Never heard that before.... Anyway, fair enough, part of what is important here is that calling me a stereotyper is something vastly different than calling me a raccist. That would be accurate. Just like, "Italians make great bicycles." That's a stereotype. Massive difference. Stereotyping organizes our cognition, we make attributions in loose stereotypes millions of times every day. We organize information without volition , it's just what we do, cognitive psych 101. Calling someone a stereotyper is not employing hate speak, calling someone racist is. Especially when the accuser can't explain what racism even is. That's a powerful thing to call someone. You should have a clue what you are saying if you do that and you should be absolutely willing to stand up and be responsible for the accusation, and if you are right, stick to your guns and address it and stomp it out. Hurling it at someone and running off is cowardly and even worse, shows you have no commitment whatsoever to challenging racism.


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## fflutterffly (Dec 1, 2014)

Had the Conti 4000s II 28 rear tire sidewall blow out at the beginning of a ride, smooth surface, 110 psi. The tire was only 2 months old. Helens, Santa Monica, CA replaced it ASAP. Been riding on the same tires for over 1000miles. I have them on all my bikes due to the rough surfaces on Pacific Coast Hwy. They seem to be the best wearing tire I've have used. I'm running them on Fulcrum rims. One point: I check my tires for wear at least, at least, once a week. Regardless if this guy is an idiot or not, biking is dangerous, downhills at 40 mph in your lycra underwear and crashing will cause sever damage to you. Check your equipment and don't inflate to top PSI.


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## PBL450 (Apr 12, 2014)

fflutterffly said:


> Had the Conti 4000s II 28 rear tire sidewall blow out at the beginning of a ride, smooth surface, 110 psi. The tire was only 2 months old. Helens, Santa Monica, CA replaced it ASAP. Been riding on the same tires for over 1000miles. I have them on all my bikes due to the rough surfaces on Pacific Coast Hwy. They seem to be the best wearing tire I've have used. I'm running them on Fulcrum rims. One point: I check my tires for wear at least, at least, once a week. Regardless if this guy is an idiot or not, biking is dangerous, downhills at 40 mph in your lycra underwear and crashing will cause sever damage to you. Check your equipment and don't inflate to top PSI.



110 sounds kinda higher a 28 no?


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## Oxtox (Aug 16, 2006)

PBL450 said:


> 110 sounds kinda higher a 28 no?


guy must be on the husky side.

I don't even take 23s that high...


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## PBL450 (Apr 12, 2014)

Oxtox said:


> guy must be on the husky side.
> 
> I don't even take 23s that high...


Yeah, agreed, me either, and on some folks accounts at the 100-105 I ride on 23s is a lot...


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## Migen21 (Oct 28, 2014)

I'm beyond "Husky" at 6' 5" and 235lbs. I run my 28mm 4 Seasons at 75 front and 85 rear most days. If I'm feeling really frisky (and going for a short/fast ride), I might bump it up to 85/95. 

110? No thanks, I'll pass...


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## Lombard (May 8, 2014)

PBL450 said:


> 110 sounds kinda higher a 28 no?



Yes, that's high for a 28, but it shouldn't cause a sidewall to blow. It is just unnecessary.


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## fflutterffly (Dec 1, 2014)

The conditions warranted the pressure. This isn't the point. The sidewall gave out. First time in 40 yrs of cycling and racing I'd ever had that happen. And yes I'm a clydesdale gal.


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## Lombard (May 8, 2014)

fflutterffly said:


> The conditions warranted the pressure. This isn't the point. The sidewall gave out. First time in 40 yrs of cycling and racing I'd ever had that happen. And yes I'm a clydesdale gal.



Get yourself a pair of Maxxis Re-Fuses and save yourself the future inconvenience of a very painful faceplant.


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## SPlKE (Sep 10, 2007)

fflutterffly said:


> The conditions warranted the pressure. This isn't the point. The sidewall gave out. First time in 40 yrs of cycling and racing I'd ever had that happen. And yes I'm a clydesdale gal.


Aren't clydesdale gals called Athenas?


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## Lombard (May 8, 2014)

SPlKE said:


> Aren't clydesdale gals called Athenas?



I thought they were called clydettes.


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## fflutterffly (Dec 1, 2014)

Never have done a faceplant, but thanks for the suggestion.


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## Liptrap (Feb 13, 2021)

BruiserBob said:


> *Continental Grand Prix 4 Season Sidewall Failure*
> 
> View attachment 314034
> 
> ...


Same - 4 years later. Hit the road post-COVID lockdown in January 2021. Bike hadn't been ridden for a year and the Continental 4000s were only a few months old when last on the road. Thought I was seeing things when I noticed inner tube bubble poking through side wall. Stopped and saw the whole side wall threadbare. Cautiously rode home but the inevitable happened. Luckily I wasn't hurt. Any news on Continental's response (if any)?


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## Liptrap (Feb 13, 2021)

Migen21 said:


> Would you mind linking other instances of this happening with this tire? PM if you prefer? I've been riding this tire for a couple of years under the impression that they are safe and reliable. I'm keenly interested to know that this isn't the case.
> 
> I haven't had so much as a flat tire on mine in over 2 years of riding them year round, some if it on crappy roads in crappy pacific northwest weather.
> 
> ...


Continental has a problem still so yes, you can question their manufacturing. January 2021 I hit the road post-COVID lockdown. My competition bike hadn't been ridden for a year while training on my Zwift set-up and the Continental 4000s were only a few months old when that bike last used. Thought I was seeing things when, while stopped at an intersection, I noticed inner tube bubble poking through side wall. Closer inspection showed the whole side wall threadbare and coming apart. Cautiously rode home but the inevitable happened. Luckily I wasn't hurt. Sounds like Continental and its supporters (and I have been one previously for over 20 years) may have their heads in the sand if they think there is no systemic problem.


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## Lombard (May 8, 2014)

Liptrap said:


> Same - 4 years later. Hit the road post-COVID lockdown in January 2021. Bike hadn't been ridden for a year and the Continental 4000s were only a few months old when last on the road. Thought I was seeing things when I noticed inner tube bubble poking through side wall. Stopped and saw the whole side wall threadbare. Cautiously rode home but the inevitable happened. Luckily I wasn't hurt. Any news on Continental's response (if any)?


I have had bubbles happen on Bontrager and Specialized tires. And I have been with someone who also had a bubble in a Bontrager tire.

A bubble is a defect that can happen. You will usually know when you hear that thump, thump, thump. If it's a front tire, walk home. If it's a rear tire, ride home carefully.


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## OldChipper (May 15, 2011)

Had this diversity of experience with a buddy of mine. I rode GP4000 forever with no sidewall issues, he had several failures. Turns out he was riding his at like 110psi whereas I was at 95 (and I'm like 15 lbs heavier than he is). He reduced his pressure and voila! No more problems. I realize that the tires are supposedly rated to like 125 psi, but no one who's not on the track needs to use that pressure. You might try that.


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