lyrictenor1

I've read quite a few people mention that the Conti GP4000s ii tires have weak sidewalls; I too have a sidewall fail on me as well with one of these tires.

I noticed as I put more and more miles on a couple of my tires that I can start seeing some threads (is it the casing?) on the sidewalls after a while. Is this indiciative of sidewall wear?

andr0id

What is more and more miles in numbers?

They seem to have good tread left on them.

Andrew R Stewart 

Not saying that this is the case here but this kind of "wear" can be from underinflation. As the sidewall flexes more the stress between the ply's threads is greater. Thread separation is more likely. Andy.

lyrictenor1

Appx 2800 miles at this point. The tread wear indicator hadn't yet disappeared.

Regardless of the tread, I'm speaking about the sidewall of the tire.

lyrictenor1

I weigh 180 lbs. and I run 105psi F/ 115psi R. I check air pressure religiously before every ride.

andr0id

Yeah I see that. I run the same tire in 700x25 and don't get the worn sides.

Do you ride off road or through large patches of gravel on paved roads?

Is your rack or some other place you're storing or transporting your bike scuffing or rubbing the sides of the tires?

If you have a car rack, does the tire end up near the exhaust?

Those are the only things I can think of...

Andrew R Stewart 

The rhythmic "wear" bands of the side walls are most likely where the plys overlap. Like handle bar tape that shows wear at it's edges first, a tire will often show wear at the edges of the fabric plys.

Again My following comments are not meant as an indictment of the OP or anyone else, just observations. I wonder what width the tires are. The narrower the tires get the greater the casing loads are. 2800 miles for a performance tire isn't a bad life span. They are made to perform as well as the company can design and produce, not for as long as the public wants. That the rubber compound hasn't worn much is not an indicator of the amount of stress the tires see. If the "wear" was an incident (rock scuff, exhaust/heat) the issue would be site specific.

If one wanted to reduce this "wear" then a wider tire or a tire with thicker side walls would be the first two suggestions. Andy.

FBinNY 

IMO the tire is 100% OK showing only normal age (not wear) related signs.

Understand that the fabric tire body isn't woven but, instead made of 2 unidirectional plies laid one on top of the other at right angles (45° to the line of the tire). Because the plies are very delicate and hard to handle until laid up, some makers glue a stabilizing thread across them at interval. This serves no function once the tire is assembled, but can show out through the thin gum coating, and that's what you see at those 1cm or so intervals.

With normal abrasion in handling, and over time, these threads can become more visible, but since they no longer serve any purpose, it's only a cosmetic issue and can be disregarded.

rm -rf

I see the same repeated "wear" on my rear tire. I never noticed it until I used a flashlight on it tonight. Woah, it looks quite serious at first!

But it seems to be cosmetic. The rubber layer on the sides over the fabric is extremely thin, more like a black paint than a tire layer. The fabric is just fuzzing out where it's the thinnest. I can't feel any bumpiness there at all, so it seems to be holding the tire pressure, not failing.

3 or 4 years ago, I had one GP4000S start to fail where the side fabric split and frayed, enough to see a small bubble of inner tube starting to poke through. I patched it with a folded dollar bill for the ride home. There were other reports back then, perhaps there was a bad batch of tires. No problems since with more GP4000S or GP4000Sii

These are 23c on wide Ardennes+, 25mm wide rims. (the tires measure between 26mm and 27mm wide when inflated.) I'm about 170-175 pounds and use 80-85 psi front, 95-100 psi rear.

~~~~~
Here's the worst section. Fuzzy! I'll definitely check them after riding, but I don't see a need to change tires.

lyrictenor1

No, I only run off road very rarey with these tires, and usually only if it's necessary.

The bike sits on the top of the car in a Seasucker rack, so it's nowhere near the exhaust. I'm using the upgraded ladder strap for the rear wheel holder of the Seasuckerx and the inner surface of the strap that fastens the wheel to the rack is smooth.

jfowler85

Underinflated tires.

lyrictenor1

I run 105psi F / 115 psi R, and check them before every ride, so I don't think underinflation is the issue. I weigh 180 lbs. These are 23mm tires on 21.6mm rims (Reynolds Assault - older model).

lyrictenor1

Thanks for your responses, all. I was curious about this because the GP4000s ii are known for having sidewall failures, but maybe it was a bad batch of them, as one of the posters stated above.

jfowler85

180lb rider on 23s...that could possibly be the issue.

lyrictenor1

I highly doubt it. Never have I heard or read that riders my weight cause undue strain on 23mm wide tires.

jfowler85

Depends on the tire. Also, anecdote is not objective evidence.

lyrictenor1

Agreed; never did I say that it was objective evidence.

However, the only guideline the manufacturer placed on the tire itself is the maximum inflation pressure, which is 120 PSI.

FBinNY 

With respect, 180#s on 23mm tires isn't an issue if they're inflated properly.

In any case, there's no issue with the OP's tire. What the photo shows is a normal aging pattern on tires of this type.

Weight related wear would manifest differently, with a wider wear track in the center tread, and usually checking or stress cracking in the tread's edges because of excess flexing.

jfowler85

Again, depends on the tire. Center wear track cannot be adequately assessed from the posted photograph. Unless you have one of the photo enhancers from Blade Runner.

fietsbob

Those with the added "Gatorskin" sidewall mesh may be better for you ....

FBinNY 

Have it your way, I've explained it in a prior post and am not invested beyond this.

I invite the OP and anyone else interested enough to look at the photo in the OP, then read post #8 , then look at the photo again, and draw their own conclusions.

jfowler85

You're invested enough to keep replying. Again, center tread wear cannot be adequately assessed from the posted photo. Good knowledge drop on tire manufacturing though, keep it up.

well biked

+1. These tires are marketed and perceived by the riders that buy them as having excellent ride quality and light weight. Those two traits, generally speaking, reduce the durability of the tire. 2800 miles isn't bad at all for this class of tire.

oldbobcat

2800 miles is excellent for any road tire weighing less than 300 grams.

Plimogz

Presumably the OP feels that the tires have enough life left in their center tread that wondering about the sidewalls is important.

In any case, based on the pictures, those sidewalls look just fine. Ride on.