Reply With QuoteGlad to hear that they're taking care of you!!!
Any seconds for awarding Holly's Miata to JRW this week???
Kumho Ecsta V700 tread delamination
Here is the Kumho story from the last event.
This was the 4th event on a set of Ecsta V700s that I bought in February. After the PCA school, I had noticed what looked like a cut across the tread on all 4 tires. It did not look that deep and there did not seem to be any separation in the tread etc. At the ER event on Sunday, after my 4th run, Tailchaser noticed a large chunk of rubber that was pulled loose on the outside right front tire. Further examination, the cut was all the way to the carcase. I pulled out of grid and changed to street tires. It looked to me like someone had taken a sharp knife and sliced each tire. The cuts were deep at the edges but they did not score the carcase. JB pointed out that the cuts were at the same angle (like a bevel cut). He thought it looked like the tread belt was separating from the carcase and suggested I take them back to Discount for an opinion.
I took them by Discount this afternoon and the Assistant Mgr. examined them and agreed that it was very unusal. He called Kumho in Ca. and explained what he saw to the tech rep.
Bottom line - 4 new Kumhos, they said they will ship 2 day in time for mounting on Friday. Kumho did not admit to any defect etc, but this is a different experience than other people have had with Kumho.
I am encouraged they stood behind them and it did not hurt that this was the 4th set that I had purchased from them.
Glad to hear that they're taking care of you!!!
Any seconds for awarding Holly's Miata to JRW this week???
Aye!Originally Posted by tailchaser
(Glad they're doing the right thing for you JRW)
Hmm... this isn't the first report I've heard of recent Kumhos coming apart.
Glad to hear that you got a free replacement set out of Kumho, and hope this set lasts for a longer period of time!
Iain
"We don't stop playing because we grow old, we grow old because we stop playing." - George Bernard Shaw
Yea-free replacements are always a good thing!
You may want to drive on the new ones a little slower, maybe they would last longer! **
**Kestrel I relayed your message!
Unfortunately, he'd have to drive a lot slower to do me any goodYou may want to drive on the new ones a little slower, maybe they would last longer! **
**Kestrel I relayed your message!
"That which does not kill us, just makes us madder"
Cletus Nietzsche (Friedrich's half-brother on his sister's side)
I was surprised at free also. I can't help but be suspicious that they know of a problem with manufacturing etc. Maybe the 710 will be available in 16 inch by the time I need new tires.
Well, I just picked up my new Kumhos.
Isn't there always a hitch?
I got 2 with the autocross compound K6A and 2 with the harder European racing compound K8A.
I'll guess I'll mount the 6s on back and the 8s on front.
Kumho rep told the Discount Mgr it was a mid mould fault.
Are they going to get you a matched set??
I just got back from the BMW event.
Both of the K6A tires have the mould fault. The brand new replacement tires with 8 runs. The K8A tires look fine.
Has anyone else run into this? I was wondering if it is 16 inch problem only.
Dang we just can't get you nice things without you tearing them up!
I think Tailchaser is our only other 16" Ecsta guy, I can't think of anyone else with 16's....
There is a thread on the pointy bd. regarding more delamination issues with Kumho tires....
http://forum.miata.net/ubb/ultimateb...c;f=4;t=003426
If the 710s are K6A (Could the General or altiain check a sidewall and verify?), it sounds like Kumho has a compounding issue...
Hey guys you need to read this, page down to skod's posts!!!!
http://corner-carvers.com/forums/sho...threadid=15824
Although it seems to only apply to the 710's!
Thanks for that link POS... it was interesting reading. Just to add a little more to the conversation, I was on Tire Rack's site this morning, all ready to order my V710s. I noticed that they didn't seem to be on the site at all -- not listed as out-of-stock or unavailable, but gone from their site completely. So I eMailed them asking what was up. I'll let you know what comes back.
The problem for me is that I've got to have new tires now, or keep getting spanked by the fast guys. I guess this means I'll be on V700s, but there won't be any free V710's in my future. Serves me right for waiting I guess...
"That which does not kill us, just makes us madder"
Cletus Nietzsche (Friedrich's half-brother on his sister's side)
From the Tire Rack:
Kumho Tire U.S.A. notified us today they have chosen to voluntarily recall all ECSTA V710 tires. If you still have ECSTA V710 tires (new, used or even worn out), Kumho has authorized us to exchange them on a one-for-one basis with an enhanced version of the ECSTA V710 when it becomes available in approximately 60-90 days.
In order to compensate you for any inconvenience, as well as mounting and balancing costs, Kumho has further authorized us to provide either ECSTA V700 or VictoRacer V700 tires, again on a one-for-one basis, at no final cost to you. Since ECSTA V700 and VictoRacer V700 tires require tread shaving for use in dry conditions, shaving will be available at no charge. Heat Cycling will also be included at no charge if your ECSTA V710 tires were heat cycled by the Tire Rack originally.
The Tire Rack Team wants to help you replace your voluntarily recalled tires as quickly and conveniently as possible. If you still have new, used or worn out ECSTA V710 tires:
Contact the Tire Rack representative indicated on your original invoice, or call (800) 428-8355 and asking for the first available sales representative.
Provide the phone number where your credit card bills are received, the invoice number of your ECSTA 710 purchase and/or your name.
Identify the quantity of new, used or worn out ECSTA V710 tires you will be exchanging.
The Tire Rack representative will establish a no-charge backorder at The Tire Rack for the enhanced ECSTA V710 tires when they become available, as well as place an order for your ECSTA V700 or VictoRacer V700 tires. We will charge your credit card when we ship your ECSTA V700 or VictoRacer V700 tires.
Contact a Tire Rack representative when your ECSTA V710 tires are dismounted and ready to be picked up by the UPS representative and we will issue the required number of prepaid UPS Pick-up Labels for you to return your ECSTA V710 tires.
Upon the return of your ECSTA V710 tires, we will credit the full value of ECSTA V700 or VictoRacer V700 tires to the credit card used to purchase them.
The Tire Rack apologizes for any inconvenience this causes.
--------------------------------------------------------------------------------
The content of Kumho's announcement is provided below:
IMPORTANT NOTICE FOR ECSTA V710 TIRES
Kumho Tire’s priority is safety, and we are committed to supplying our customers with the highest quality and best performing tires that are available anywhere in the world. It is with this philosophy in mind that Kumho is taking immediate action in discontinuing the sale of the ECSTA V710 Competition Tire.
The V710 has won several races and set numerous track records since it was introduced into the market on January 1, 2004. Although we have not experienced any air loss failures with the ECSTA V710 Competition Tire, we have discovered some inconsistent test results relating to tread splice and tread area durability.
The sale of the ECSTA V710 Competition Tire will, therefore, be discontinued immediately, and tires in use in the market will be collected from consumers. Kumho will replace them with either the Kumho ECSTA V700 or Victoracer tire free of charge.
An investigation into the cause of the inconsistencies has been carried out and modifications to the product and production methods have been made to ensure these inconsistencies do not re-occur.
Consumers who have purchased the ECSTA V710 Competition Tire must call the dealer where the tires were purchased or the following toll free number to arrange for tire return and replacement:
1-800-445-8646 Extension 342
Consumers will be given the choice of a free replacement of the ECSTA V710 with either the ECSTA V700 or Victoracer. They will also be provided a free set of the modified ECSTA V710 upon its arrival.
Kumho is sincerely committed to the quality of our products and the total satisfaction of our customers. We regret any inconvenience to our customers.
Kumho Tire U.S.A.
14605 Miller Avenue
Fontana, CA 92336
David Smart
Mazda MX5 Club - STR 194
UPDATE
Kumho has changed from, we are sorry for the problem, to ignoring my phone calls.
I just ordered a set of Hoosier tires so I will have something to run this weekend.
Yikes! What happened? Is you discount tire guy having any luck with Kumho?
Discount is getting the same run around.
Kumho is denying sending me the replacement set of tires and I have been leaving messages for 2 weeks trying to get someone to talk to and have had no luck.
Follow up
The motorsports manager, Rudy, called me back today.
Very nice polite etc.
They are going to comp me another set of Ecstas and this time they will shave them.
He also said they are thinking of recommending a nitrogen fill for the 710's.
He also said the second tire test for the redesigned 710s will be next week.
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