Are my new tyres faulty??

too_sleepy

Hi

Purchased some new tyres a few months ago. Continental Grand Prix 4000s. They've developed some cracks on the side wall of the tyre. Actually the crack is all around the side wall. Looks like the tyre dired out and cracked; Is this possible??

Thanks

Lumen

pic?

macnab

check the sidewall for a date of manufacture, motor vehicle tyres have this, not sure about bicycle tyres. It should look something like ABC1209 - which is the 12th week in 2009.

too_sleepy

Hi

They don't look so bad in the pics.

Pic 1

Pic 2

Thanks

G rock

have the same tires as you and have just checked them to find out that i have the exact same problem.

hoping they don't explode on me on the way home this evening!

blorg

I had that with a pair of tyres but it never caused a problem. Think it was GP4000s.

GT_TDI_150

if they were car tyres i'd say they had been driven on while (partially) flat, that what the look like to me

too_sleepy

Hi

Well they certainly have always been inflated correctly. I have a Continental Ultra Race in use also and it shows no cracks. The Ultra Race has been in use far longer.
I'm going to write to the manufacturer, not a complaint, just to check if they're alright to continue using.

Would be good to know if many others have these tyres and the condition of the side wall.

Thanks

sean_d

Just checked my GP4000 - it has the same crack in the sidewall.
Definitely hasn't been ridden flat at all

another world

I bought the Continental GP4000s a while back and on the first cycle it blew up. A good part of the side wall had a hole in it. Seems to be a problem with them from some of the comments here and what I've read elsewhere. In fairness, CRC sent me out a replacement which seems ok but I'm constantly aware of it!

Murph100

I dont like the look of that at all !

Hail 2 Da Thief

I put a new pair of GP 4000s tyres on my bike a few months ago too. They do not have sidewall cracks like that. Looks dodgy imo!

seve65

I have had several small cuts in the gp 4000s I have had, but I have been on some pretty bad roads so im not too surprised, they didnt puncture though through the cuts. Only punctures have been pinch punctures hitting pot holes. I have just had my second larger split causing need for second replacement tyre since last May, not sure whether to blame the pot holes for those. Anyway I dont and didnt have the crack that you have.

macadam

My Conti gp4000s are the same and never cycled flat, its as if the side wall was coming away from the tyre itself.

too_sleepy

There was a spare GP4000s in the shed, never used. Actually hadn't been taken out of the box. It also has the same cracks. I've taken more photos and have an email to send to the manufacturer.
I'll post any reply I get.

jdt101

been using gp4000s's for the last 3yrs (racing and training), no problems, very few punctures. run at 120psi.