I have the Continental Grand Prix 4000 tires on my cycle. One has the black chili compound and the other does not. I have just noticed the fibers near the rim have started coming off all around the tires on both sides. It sort of looks like a little groove all around the tires now. Has anyone else experienced similar issues? I still have good tread but I am now concerned about the sidewalls. Are these safe to ride on for training? I sent an email to Continental.
Funny you should post this… I was just out riding last week on the exact same tire - 3 weeks old and kabammmm! My front tire exploded @ 23mph. After inspection of the tire, I noticed the side wall separated from Kevlar bead and the tube exploded because there was nothing to hold it.
I chalked it up to a freaking thing but now I am thinking again.
Me too. Twice this summer. Both times on my rear wheel. I assumed it was rubbing on the seat or chain stays. Maybe not, there seems to be enough space. Let us know Cont’s repsonse.
same here, happened to one of my GP4000s, on the rear tire, assumed it was rubbing a chain stay as my road bike tends to let the tire get real close to the left one all the time.
but maybe they have had a bad batch?
The thread for the fabric for the bead starts to run, I get it when they are old, and more so when I run 25s than 23s…more acute fold at edge of Hed C2 rim, my guess…just watch it…been that way since the 3000, as well.
Ditto. Decided after last tire blew the sidewall out I will not go back to those crappy tires.
Well I guess I am not alone with this issue. The fibers are coming off a little above the rim and not where the tire seals to the rim. It is amazing that it completely circles both tires on both sides. I have yet to see this with any other tires. I have some photos but I can’t seem to figure out how to save them into this post. I will post what Continental replies. By the way these are the 23s and not the 25s.
This has happened to me on about 50% of all Continental clincher tires I have ever used, then the sidewall tears or bursts before one uses up the tread.
Same here. Completed IMC a month ago with the tires in this condition and no problems yet.
If this seems to be an issue with the Continental clincher tires what have you switched to with success? I am looking for a high mileage training tire with puncture protection. Actually the Grand Prix 4000s were initially recommeded to me by members of this forum as a great tire.
Me too. The GP 4000 tire was only a couple of months old and I had sidewall blow out when my ride was over . I was taking off my shoes and KABLAMM the tire burst at the bead. My bike was against the wall when this happened . I really liked Contis but will buy a different brand from now on. Not worth the risk.
When you say “the tire burst at the bead” what does that mean exactly? Be nice to see some pics…
I’ve had them fail parallel to the tire bead and perpendicular to the tire bead.
Gave up on Continentals but these were a gift so I used them in spite of prior experience. The GP4000.
http://www.flickr.com/photos/swoo/3161129614/
I use my old race tires as training tires, and am not looking for high mileage/puncture protection out of them, can’t help you there, sorry.
http://oi54.tinypic.com/2wceflu.jpg
That section of bead separated from the tire.
Is the bead Glued on, woven in?
I have the same issue with my 4000s. Will go a different direction next time.
If this seems to be an issue with the Continental clincher tires what have you switched to with success? I am looking for a high mileage training tire with puncture protection. Actually the Grand Prix 4000s were initially recommeded to me by members of this forum as a great tire.
vittoria rubino pro, good sir.
i have half a dozen of the older rubino pro & pro2 that i have yet to work through, but i have used the newer pro3 in 28mm diameter (used on my commuter with rear rack, fenders, etc.).
i get about 4000km out of a 25mm rubino pro on my rear wheel (for reference purposes, i weigh ~160lbs).
the pro3 moved up to a 150tpi thread, whereas previously it was 120tpi. this will likely lower the durability of the tire, but i have no idea by how much (haven’t used the 28mm tire sufficiently to go through one yet).
at ~$22 a pop, though, i’d contend that it’s worth a try before dropping more coin on another set of gp4000 tires 
That section of bead separated from the tire.
Is the bead Glued on, woven in?
I’ve had a few wee strings come loose around the bead but no separations. The picture is poor but that looks like a cut. Any chance that the edge of the brake pad touched there when closed?
Nothing new or out the ordinary was done to my 2004 Orbea roadie. Brakes did not interfere with the tire. Just an unexpected blowout
Count me in … Been through three tires this season. I will be changing brand I think.