danallen

I have had no trouble on Continental 4000 Grand Prix Sii tires. However, was just reading tire reviews on Continental 5000 Grand Prix and Gator Skins, and there is recurring pattern of tires blowing sidewalls or beads, while still almost new. Not everybody, but not just one guy either.

The people say they have been riding for years without this happening.

What say you?

Faulty tires a certain percentage of the time?

Hit something they didn't know they hit?

Installed wrong?

There has to be a reason. Is there a best likely guess?

rubiksoval

The 1st picture and the 2nd picture are two different things. I've never seen or heard of anyone I know experiencing the second.

Carbonfiberboy 

The 4000 and 5000 have similar sidewalls and I expect about the same vulnerability. I really try not to hit the sides of sharp rocks about the size of golf balls. I'll use both until my 4000's run out. Our tandem came with Gatorskins. I took them off after the first couple of rides. Incredibly slow tires.

I've had sidewalls cut like in the first photo on several tire brands, but never saw or heard about anything like the second photo - other than on the web of course. Ah, of course: brake pads were set too high, wore through. Rim probably had a wobble in it. That's the reason I've never seen anything like it.

znomit

Guilty.
Two mystery rear flats after a 100km rainy downhill towards the end of a 400.

I have abused my GP4000s in many ways. Gravel roads tend to make the reflex strips come away. No sidewall cuts.

canklecat

Dunno, I have thousands of miles on Conti Grand Prix Classic skinwalls and their low cost Ultra Sport II, no problems. Few punctures in three years and no sidewall failures. After a year on the Grand Prix Classics (with only a single flat, snakebite from running over a rock) I may switch to those completely. My only gripe about the Ultra Sport II was the fit was so tight I needed a Kool Stop bead jack to mount them. No problems mounting the GP Classics by hand.

Bah Humbug

It was claimed on the 4000S as well, even before it was the SII, so it's not new. They have thin sidewalls; inspect regularly and use fresh ones when it's important. Or do what I do and run tires with bead-to-bead Kevlar for training.

Germanrazor

I have not seen or experienced this. I don’t doubt it happens, just not heard of it widespread in my area.

Ogsarg

If a product has any weakness, no matter how slight, it will be magnified 1000X on the internet.

Aladin

LMFAO... Homerun. Exactly.

It NEVER has anything to do w user abuse... etc... . NEVER a case of running said rubber at 120 psi's and above on HOT days on HOT asphalt.. which means psi goes waaaayyy ... up.

friday1970

I've seen one sidewall of a GP 4000 SII being blown out. It was a tour out of Fenton MI, if I recall correctly. A female cyclist had to make a call of shame when her sidewall blew out.
I've got three sets of GP 4000's and a single GP 5000 set across 4 bikes. No problems on any of those, minus the occasion shard of glass flat.

mercator

I had a pair of GP4000s fail similarly to the second photo - bead separated from the tire. Put me off Continental for a while but I assume it was a manufacturing defect that affected only a few batches.

tankist

I cut my back wheel GP5000 similar to the first photo after riding over a freshly broken bottle. I don't think the tire was defective.

MSchott

Agree. GP4000's have been my go to tire for years and have proven to me to be smooth and very reliable. The last flat I had was a pinch flat. My current tires are 23mm models that I bought a few years ago prior to the trend towards wider rubber. I'm 200 pounds and ride them at 80-85 PSI.

Aladin

And that underlines the main advantage of tubeass.. I've run them down to ~ 10 psi getting home for repairs. I do not normally run seal-NOTS.. which some flavors work fine for that task.. if one monitors they 'dry state' closely.

I use the worms mostly for TL repairs. No tire removal.. easy.

Have at times.. used Super Glue gel.. sets up quick.. as it's setting I push it into the hole recess w side of tool. Has worked well few times I've done this. Some write of using rubber like cement for repairs.. drying time though prevents fast repair.

Rides4Beer

The first pic looks like they ran over something sharp, any tire would have probably gotten cut. No idea what happened in the second pic. Most of the pics I've seen of "sidewall issues" look more like "people not paying attention" issues and running over debris.

I've had multiple sets of 4000s and 5000s and have never had a sidewall issue. I've had one tire damaged from hitting a big pothole, but I'm pretty sure that would have happened to any tire (a lot of people probably would have kept riding on that tire, only had a small hole in the sidewall, but I like my teeth so I scrapped it).

Psimet2001 

I've had a lot of customers with 5000's who have tire failures rapidly after putting a new one on. I always remark how almost everyone seems to have one with these. Then they bring them in and I can tell they ran over something and cut them. *shrug*

At this point I won't say that I think the 5000's are garbage. Honestly I see so many likely because there are so many people riding them as the internet has no tolerance for more than one go to tire for performance. Personally I have thought top Conti tires are complete crap and have been for a long time. I had hopes for the 5000 as the compound is more like what others have had for a while (vittoria, Pirelli, Michelin) so they are softer and give a better road feel. I am now not as hopeful and I will continue to ride whatever else is a top tire. (Except Schwalbe...seen too many complete weird failures with them and inconsistencies)

Voodoo76

I've had one GP4000 failure that was a good 3" long separation at the bead a few years ago. Rear tire, at the time about half a season on it. No major impact or anything, started feeling a bump in the tire immediately followed by a blow out in dramatic fashion. I've ridden many miles on 4K's and a set of GP-TT's since then, as I had a few pairs on the shelf. But I'm going to try Vittoria or Michelin after this last set is worn out.

sfrider 

Definitely keep them away from large debris like rocks. I've had 4000's (though never 5000's) "herniated" where there is marginal sidewall damage, just enough for a bulge. I consider that a complete loss and I replace the tire. It tends only to be older fairly worn tires that are susceptible to this though, and I know it's because I'm careless with them. I tried a set of Michelin Pro Race 3, maybe 10 years ago or so, and had a 2" rip in the sidewall on the first ride. Had no idea if it was something I did to them (most likely) or a manufacturing defect (remotely plausible). I replaced them with GP3000's (so it probably was more than 10 years ago) and if something works I'll just stick with it. One nice aspect of riding a popular tire is eventually I can stock up when a bargain manifests itself. The 5000 TL is probably a bit too new for this, but one of these years they will be available at half off or something - and I'll nab a 5 year supply.

Red Bank Steve

Just had it happen to me (second picture). About half season on tire, felt some thumping and BOOM

stevel610 

I've been riding GP5000S for about 600 miles. A couple dozen of those on gravel. No problem so far.

Iride01 

I've got two bikes with GP5000's on them, the tubed version. Both sets over 3000. One bike might be over 5000 miles. I've never had any issues. Very few flats. The bike with 3000 miles on it's tires, no flats.

I did have a sidewall cut on my Specialized turbo cottons, but hey, a cut is something I consider a user issue. I should sweep the trail before riding on it or something. Or maybe just not run over or next to sharp stuff. So any tire one gets will have that at some point if you ride it long enough.

The other picture looks like either the rim brakes were riding the tire sidewall or the tires were regularly ridden with very little air for a very long time. But I'm also open to the possibility it could be a manufacturing issue. But out of the seven or so GP5000's I've used none have so far ever had an issue. One just wore out.

I rode Vittoria's for quite a while too and they were great problem free tires for me. But they quit making the version of the Rubino Pro that I was using so I thought I'd jump on the GP 5000 bandwagon. And I don't have any regrets since changing over about 2 years ago.

bbbean 

Define "recurring pattern".What percentage of Conti tires show this problem? Verified by third party? How many samples? How does this compare to other brands/models?

MinnMan

The wire bead separated from an older studded winter tire. Winter tires normally last years because the tread is so thick, and I just figured that the rubber aged and got brittle.

I've posted this pic to bf a bunch of times - it's about 10 years old. It was a rather new GP4000. Riding in a pace line, somebody in front of me hit a rock and it ricocheted into me. Underneath is a ParkTool tire boot that got me home. I had something similar happen a few years later when I ran over flattened aluminum can. But I ride GP5000s now and no similar incidents. Statistics or luck, and thin side walls that go with a tire that has low rolling resistance.

GhostRider62

I have probably gone thru 15-20 GP5000 tires and scores of GP4000. I had one casing semi-rupture on the GP4K but I was bombing down a gravel hill. No failures on the GP5000 tires. OTOH, every single Compass extra legere casing ruptured on me.

Bead separation sounds like something sharp cut it, something like carbon.....I wonder what could do that?

Branko D

First looks like a cut from something sharp, the tires are rather resistant to cuts on the thread but sidewall, no.

Personally, rode about 13000km on GP5000s without any issues.

They are a very popular tire so you'll find a lot of issues online just because of how common they are.