Kumho ku39 - Has anyone ever had this happen?

[Lavery]

Anyone ever seen a kumho ecsta ku39 do this before?
It's on the inner side of the tyre.



Think I will be making a call and sending an email to kumho.
Looks like a manufacturing default to me. Tyre has only covered 7000 miles.
Been wondering why it loses pressure frequently.

 

[RUM4MO]

One thing, is that truly the cause of that tyre losing pressure, or not just the effect of that tyre being used while very low on pressure. I ask that question as it could be losing pressure at the valve/wheel area or around the rim due to corrosion, I've been there done that after not being able to find a puncture site. I'd think these are questions that the tyre place will ask you and probably check the wheel/tyre in front of you to make sure that that is not the root cause of that separation at the firm side wall pliable tread junction.

 

[Lavery]

Not sure if it's the cause of the tyre losing pressure but the splits certainly arent the effect of running on low pressure. I never let it get too low, always keep topping it up.
I'll have to take it to a tyre shop, like you say and get it checked!

 

[RUM4MO]

I'd reckon that is what you should do as it is them and not the tyre manufacturer that you need to deal with.

I had an issue once with a Goodyear NCT supplied fitted to a new Ford Orion Ghia, it had developed a "flat section" - needless to say, even though I did the right thing and took it into a tyre place that dealt with Goodyear, they conspired to lose the tyre and awarded me a voucher for their exhaust/tyre services up to the value of the percentage of the tread left! Now that was not handy as I planned in selling the car before I'd need to change the exhaust or tyres, seem to remember I cut my losses and sold the voucher on to someone that could use it!

 

[spud31]

Mine did this same tyre after being used on out of round wheels that i wasnt aware of how bad they were.
Also our 40 series tyres take a massive hammering from pot holes

 

[Lavery]

Out of round wheels? Can you explain please mate?

 

[RUM4MO]

Out of round wheels? Can you explain please mate?

Maybe shaped a bit like 50 pence pieces, ie some non round section(s) due possible to pothole impacts.

 

[Lavery]

Is that something which can be repaired?

 

[lil3520]

never had a problem with these tyres.

 

[The Seer]

I would never buy KU 39's. I had them on my stage 1 mapped Cupra TDi when I bought her. Even in the dry there was too much torque steer. Do yourself a favour, spend the extra 30-35 quid per tyre and buy proper performance tyres. I opted for Michelin Pilot Sport 3's, far far better.

 

[jambon]

Out of interest what mileage are you getting on these tyres? I bought the same and 3,800 miles later they are close to legal, that's just since 11 November..... I don't particularly rag my car either. Wear is completely even?!

 

[The Seer]

Out of interest what mileage are you getting on these tyres? I bought the same and 3,800 miles later they are close to legal, that's just since 11 November..... I don't particularly rag my car either. Wear is completely even?!

I've had em' on since September, I reckon I must of had just over 3K and there's plenty of tread left, far from the wear markings as such. Used Exalto's on my Clio 182 a few years back, used to see about 10k from them.

I don't drive the Ibiza in anger that often either.

 

[jambon]

Cheers. It's a mystery then..... bad batch?! It's not exactly been cold either.

 

[Alzak]

I would never buy KU 39's. I had them on my stage 1 mapped Cupra TDi when I bought her. Even in the dry there was too much torque steer. Do yourself a favour, spend the extra 30-35 quid per tyre and buy proper performance tyres. I opted for Michelin Pilot Sport 3's, far far better.

I have Kumho on my mapped PD170 and they holds much better than Goodyears Asymmetric which kumho replaced ...

 

[Lavery]

Grip/torque steer isn't an issue. I like the tyre... I wouldn't know what I get miles-wise as these are my first set. They've done about 8000 ish and there is still plenty tread. It gets daily driven like anybody else and a spirited drive every so often when roads are clear.

 

[G.P]

I would never buy KU 39's. I had them on my stage 1 mapped Cupra TDi when I bought her. Even in the dry there was too much torque steer. Do yourself a favour, spend the extra 30-35 quid per tyre and buy proper performance tyres. I opted for Michelin Pilot Sport 3's, far far better.

To be fair, whilst the PS3's are an OK tyre, as with every tyre Mich. produce they are designed mainly for comfort & to cover the most miles which they pride themselves on, but you can't have the best grip and a long lasting tyre.

For me I'd pay extra not to have the Michelin, they have to many issues for me..

 

[mjstokes85]

I've done about 4k on mine and the tread has barely gone down.

 

[The Seer]

To be fair, whilst the PS3's are an OK tyre, as with every tyre Mich. produce they are designed mainly for comfort & to cover the most miles which they pride themselves on, but you can't have the best grip and a long lasting tyre.

For me I'd pay extra not to have the Michelin, they have to many issues for me..

Describing the Pilot Sport's as an "ok" tyre is a bit of an understatement, they are a performance tyre through and through.

I've found them so far, as I did with the Exalto's, to offer excellent grip in all weathers. I wouldn't say they are mainly designed for comfort neither. Though I will say the comfort is slightly better than the KU 39's I had. As far as the sidewalls diminshing, as with the Exalto's that too does not appear to be an issue.

Seems quite a few others think the same as myself, as do various independent tests... http://www.tyrereviews.co.uk/Tyre/Michelin/Pilot-Sport-3-PS3.htm

 

[mjstokes85]

Just posted on your RR Lavery about this, my car failed it's MOT on the exact same issue you had, I have the exact same tyres. Both front tyres on the inside wall looked like someone had run a knife around them, you could see the metal and everything. Only done 10k and had them a year next week, always been run at 30psi, Seat say 29psi is correct, tyre place say they always put 32psi in. Took them back to the tyre place and they stuck 2 new ones on and said they have never seen this before. I had to pay for the new ones but they are keeping the old ones as evidence to show the Kumho rep who visits once every so often in a hope to get my a refund. I have just sent Kumho an email complaining as this is very dangerous and very costly, tyres shouldn't do this full stop, let alone after 10k and less than a year.
What did you do about yours?

 

[Lavery]

I did the same as you, I bought a fresh one. Mine always run at 32-34psi (34 now since the tyre split).
Will be interested to know what Kumho have to say though as this isn't safe.
Thought mine may have been a one-off so I bought the same tyre again because I like how they hold the road... Might think twice next time I swap though.