Anyone seen R comps do this?

[tju-vette]

About a week ago I found one of my V710s had a cut on the corner of the tread. I figured that during the winter one of the snow shovels or a garden spade or some other deadly yard implement had fallen against my stack of tires and cut it. All the tires have a lot of tread left so I was irritated but it's not the end of the world.

Well since then I've found two more tires have the same thing! And one of those tires was on the car and should never have tangled with said deadly yard implement.

I bought the tires in late 08 and ran a couple of track sessions on them. Used them for only 3 track sessions in '09.

Below are some pics of the first tire I found but the other two look quite similar but vary in length. Two have them on the inside edge and one one the outside edge.

Has anyone ever seen or heard of anything like this

[TroyV]

V's have done this to me when I was running an 03 Cobra in SPA. The grooves would come, then "heal" over changing appearance and character from heat cycle to heat cycle. Wierd, but the performance of the tire was always fantastic. Of course, there was a point at which I would no longer feel comfortable with running them at 120 mph on track, and busted them down to autocross only duty. I shredded them to the cord without a failure.

[tju-vette]

Was just pointed to the section below from the Tirerack website.

Perhaps this is the cause? My initial reaction was to trash the tires but from reading this, and Troy's response above maybe I don't have to?

Tire Inspections Between Sessions

Tire inspections between sessions should be used to remove all rubber pickup from the wheels and tire treads, as well as offer an opportunity to examine the tires for punctures or cuts that might lead to compound tearing or air pressure loss. The inspection should also confirm if each tire's tread compound splice (that runs perpendicular to the direction of travel across the tread area) has become visible.

A visible tread splice is caused by tearing open the tread compound junction at the tread splice. Visible tread splices are caused by the torque of the engine spinning the tires during acceleration or the stopping power of the brakes briefly sliding the tires when slowing from high speeds. Front-wheel drive and most all-wheel drive vehicles place extreme stress on the front tires from both acceleration and braking forces, and are therefore more likely to see these visible signs of use than more balanced rear wheel drive vehicles.

If a visible tread splice is detected during tire inspections, the tire should be rotated side-to-side on the same axle. This will then use the vehicle's wheel spin to "close" the splice rather than continuing to "open" it. While this may cause the tread splice to become visible on the other tire used on the same axle, the inspections and side-to-side rotations should be repeated until the tire has worn out.

NOTE: Continued use of a tire with a visible tread splice in the same wheel position will cause the tread compound to tear downstream from the splice, forcing the tire to be removed from service.

The tires on very high horsepower cars should be rotated side-to-side between every session as preventative maintenance.

[breakaway500]

Tom,I would get those small cuts on my V710's all the time on my Focus.I use to swap them diagonally after every other session,and run them to the cords without incident.

[mr2sc]

I think I already posted here about having issues with V710s, but that was after the 1st set came apart.

This was after my 2nd set came apart, it may be of help
http://www.casc.on.ca/forums/showthread.php?t=17299

[TroyV]

Thanks for the link Tommy. There has been much talk about the early tires vs the later tires. Even though this happens, and no one I know has experienced a failure using the later tires, it still doesn't mean that it should be acceptable behavior for a purpose built tire this expensive or sold at any price for that matter. It can't hurt to bring it to TireRack's attention.

[mr2sc]

well, my 2nd set that came apart were dated 0309 (3rd week or 2009). These are the ones pictured in the link I gave above. Maybe USA bound tires weren't exposed to cold storage....

Re the tread splice issue (which is separate), besides the horizontal splits on my driven rears, the fronts also developed circumferential splits all around the tire.

And yes...I swapped left/right after every day (as always)...but not "every session as Kumho had suggested in the one time they answered an email. That's ridiculous! why would I want to uninstall/reinstall and worry about torqued wheels every session? Add wear/tear to my wheel studs, wheels...and to myself?
For the priviledge of using tires that otherwise come apart? C'mon...I don't have to do that with any other tire...What a brush off!

Anyhow, I got used to the splices and wasn't spooked by them after a while and admittedly, they never actually delaminated from 'that' specific issue.

Asides from that one suggestion, Kumho never got back to me again and the only time I actually spoke to directly to 'Kumho' was by chance at Lemons race at NL last October and those guys were very nice, but clearly not 'customer satisfaction representatives'

I know others have used V710s VERY successfully (hey, mine were very fast when they weren't coming apart), but here in Canada, I don't see any being used on road courses any longer...only Auto-X.
Kumho have ruined their reputation and have shown they don't stand by their product...at least up here. YMMV

[Mario Fallas]

now i feel like a fool , i actually got rid of a set for the very same issues @ the beginning of '09, i love the V710's but if this issue reoccurs i'm out of dodge & going with Hoosier R6's
the savings using V710 VS R6's is not enough to keep me there if the things are going to fail like that, i don't care about swapping sides on the same axle crap, with the Monticello event coming up & potential 140-150MPH the thought of having a tire blow out is not exactly comforting
Mario

[mr2sc]

Maybe the ones from the American distribution network weren't exposed to the same conditions. Hopefully they'll be fine, just keep a close eye on them. See ya there (meanwhile I'm just musing about leaving my street tires on and starting off on those to avoid too much back/forth labor there as it may start out a bit wet)