Kumho KU39's - noisey or what?

[gtr1000]

I've had four Kumho KU39 (215/50-17) on my Signum Design V6 CDTi for the past 1000 miles and I'm really not enjoying the droning/humming that these tyres seem to produce. For the first 400 or so miles they produced little or no road nosie and they seem to be noisier at temps < 8 degC .

These tyres replaced part worn Dunlop SP's on the rear and Accelera () on the front which, as a package, weren't that noisey. New rear bearings were fitted both sides just 100 miles before the tyres went on. I've e-mailed Kumho UK a week ago but no reply to date.

So, to those of you that have the KU39's - do you think they're noisey or acceptable? From all the rave reviews on here and the net, I was led to believe they'd be super quiet .

[Dan_BlackSRi]

Just spend ages trying to find which ones I had on my old Vec, and it took me that long I wanted to post something. I had the 18" version of the KU31's and they were virtually silent - granted not the KU39, but would be keen to know if others find the KU39's noisy as I would contemplate these as I need some new boots.

[Ziggy]

Are they directional? If so check they are on correctly.Is it front and rear making the noises

[m8internet]

Are they directional?

No these are an assymetric tread pattern
Check that the OUTSIDE marking is visible on each

Kumho will advise you return to the outlet that fitted them
Sadly to inspect them, they will have to be sent to Kumho and will be returned to you after about 6 weeks
I would NOT recommend this unless there is a clear and obvious defect

What condition were they when fitted (used or new)?
What speed and load rating are they?
What year code do they have?
What tyre pressures are you running?
Have you compared different road surfaces (in the dry)?
Have you compared the same road surface in different weather conditions?
After fitting the new tyres did you have the front tracking checked?
What incremental weights were used on the wheels (1g, 2.5g, or 5g)?
Where on the wheel were they fitted?
Does the red dot match up to the valve?

Finally, search google for "KU39 noise" and there are loads of such reviews, especially on cars of this size

[gtr1000]

New.
95Y, XL.
Year code - need help with this one.
38F, 35R.
Road surface - same sort of hum regardless of surface.
Full global geometry set-up following tyre fitment.
1g increments - I did have the rears re-balanced by the same garage at 800 miles to try and reduce the noise and they found each rear was out by 25g . Strange cos I watched them balance all the tyres when they first went on and they were perfect.
Weights - will have to have a look to see where they've put them.
Red dot doesn't match any valve on any rim.

Garage in question is Wheels in Motion http://www.wheels-inmotion.co.uk/index.php so they should know what's what.

[m8internet]

Year code
This will be a four digit code and should end xx09 xx10 or xx11
Usually beside the batch code

The red dot is there so that tyre fitters knows where to fit the tyre in relation to the wheel
Some tyre fitters are not aware of this
The valve should be aligned next to this
Obviously it won't be perfect, but it should be relatively close
If this is NOT the case, then return and ask them to refit all four tyres correctly
Again, afterwards they will require to be rebalanced

Equally, when viewing tyres I am shocked at how many do not have the red dot aligned up correctly

As above, it seems many people are reporting these as noisey
What is the UTCQ rating on them? (marked as Treadwear Traction Temperature)

[gtr1000]

Year code = 3011, March 2011?

Taken from the sidewall (UTQG rating)

Traction AA
Temperature A
Treadwear 280

Any help m8?

[m8internet]

Year code = 3011, March 2011?

Just wanted to make sure it was no more than 2 years old
The 30 is the week number, so is W/C 18 July 2011

Traction AA
Temperature A
Treadwear 280

This is an incredibly hard tyre (treadwear above 240)
Hence the noise
Even the Goodyear and Michelin I run on mine are only 240

When considering tyres, take an actual look at what is available
A good outlet will have all the types you want (although not necessarily in that specific size)

Take notes of the UTQG (slight typo entered my OP) and compare
Basically the higher the treadwear number the harder the tyres
Equally, the lower the traction rating the softer the tyre (AAA is hard and C is soft)
Finally, only use tyres with Temperature A on the pubic road, if it has B or C do not use

My previous Michelin tyres were HX MXM 205/55R16 and these were incredibly hard with a treadwear index of 320 and traction index of AAA
They were noisey, had an extremely long life, but were poor in the wet, and that was the compromise

[gtr1000]

Thanks for the excellent info.

It would seem that if you want a quiet tyre you'd have to take into account the UTQG ratings which appear non existant for the majority of tyre manufacturers' web sites.

As you rightly say, the only way to get this info is to examine a selection of tyres at an outlet.

So I've learnt my lesson on this one - back to Uniroyal Rainsport II's next time (a long way off ) which were very quiet up to the point I sold the GSi with 12k miles on them.

[pipamish]

I have khumo ecsta 235 35 19 and I can't wait to change them as I get a vum vim vum sound