Hi all,

Just bought my SL500 which had been stored for 6 months on new tires, and these subsequently came with flat spots that I can't get rid of.

The corrections my respected tire guys recommended haven't worked. Most suggestions are along this line: run the tires at 20psi for 10-20km to warm them, then inflate to 45 or 50psi and do a long 300km run. Then deflate to correct pressure.

I've tried this a couple of times, but the vibration at 100km/hr (60mph) still won't go away. My wife hates the ride because of this, and I'm not impressed either.

Am I faced with premature changeout on these tires? I can't recall the brand since my car is in the paint shop right now, but they are not any of the big brands, and came from Japan with the car. That doesn't bode well, I know!

I'll make a change to Michelin for a new set, but would prefer to do it after I've gotten some km value from these existing tires.

Ken Silver
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~1993 SL500, glistening black/grey on black leather, now in the shop for facelift painting lower body.
~1991 Daimler, shiny grey on grey leather, best in country!
~1991 Miata MX5, sparkling BRG on tan leather, wife's - (and my polishing)
~1992 Honda US s/wagon, black/grey
ex 350SL, 230E, 280E (and a lot of other makes not nearly as nice)

replace the tires

__________________

Please, call me to place orders or for more info
use my name for on-line orders

I think there is a way they can 'true' the tire up but this involves taking off rubber until the whole tire is at the same level. I flat-spotted a new tire before by locking my brakes up for quite a distance. I just kept trying to roast the tires so it was smoother (which was sorta fun ), I also had it turned around so the toe was riding on a smoother spot. I actually sold it like this but I had some new SZ50s (from the tirerack ) waiting.

__________________
Jeff M.
Mercedes W123 DIY pages are now located here.
1983 / 1984 300D Sold
2000 CLK430 Cabriolet ~58k Sold
2005 Avalanche 4x4 ~66k

The Shop that does my Balance work ..Starts with a True tire..shaved until round with a machine that shaves the tire until its round..Then Spins it on the car and Fills it with Nitrogen for
less expansion under hard use
He Does F1 cars,Cart cars F1 Bikes and Aircraft..He Even did My Go Kart...
You can replace the tires..BUT I Have seen him True my NEW tires
So I Would find a Good Tire shop to true the tires

BoostnBenz,
Thanks - your roasting technique sounds quite exciting to do but a bit out of my league!

Mark,
Both BoostnBenz and you suggest shaving - how much tread does this remove?

Ken Silver
--------------
~1993 SL500, glistening black/grey on black leather, now in the shop for facelift painting lower body.
~1991 Daimler, shiny grey on grey leather, best in country!
~1991 Miata MX5, sparkling BRG on tan leather, wife's - (and my polishing)
~1992 Honda US s/wagon, black/grey
ex 350SL, 230E, 280E (and a lot of other makes not nearly as nice)

However much is needed to make the tire trully round.

__________________
Jeff M.
Mercedes W123 DIY pages are now located here.
1983 / 1984 300D Sold
2000 CLK430 Cabriolet ~58k Sold
2005 Avalanche 4x4 ~66k

In many cases just running them on a hot day will smooth them out. Yours is obviously not one of these cases. You will spend more time and frustration trying to salvage these tires than if you were to just simply replace them.

Shaving them, even if it works will take away treadlife and will probably not be a long term fix.

Good luck,

True, if the flat spot ever did come out then they'd have to be trued again, but that one should last the rest of the tire's lives.

__________________
Jeff M.
Mercedes W123 DIY pages are now located here.
1983 / 1984 300D Sold
2000 CLK430 Cabriolet ~58k Sold
2005 Avalanche 4x4 ~66k

Uh-huh I guess my real concern - I didn't express properly here - was, how much indentation does a flat spot make? 1mm, 4mm, more?

So if a new tire is 7.5mm and shaved down to 4mm, that's pretty much say goodbye to the useful tread, isn't it?

I'll be passing by my expert tire guys this morning, so will see what they say. Though anyone selling new tires has a vested interest in getting me to throw them away!

Ken Silver
--------------
~1993 SL500, glistening black/grey on black leather, now in the shop for facelift painting lower body. Now I know why cars have trim and bumpers... removed = yuk!
~1991 Daimler, shiny grey on grey leather, best in country!
~1991 Miata MX5, sparkling BRG on tan leather, wife's - (and my polishing)
~1992 Honda US s/wagon, black/grey
ex 350SL, 230E, 280E (and a lot of other makes not nearly as nice)

Well of course my answer was obvious, but I have no idea how much your tires are flat spotted so I can't answer that. I would think 4mm would be quite noticeable by just looking at them. Indeed it would be a lot of tread lost, they probably won't be thrown away, just moved to the used tire shelf.

__________________
Jeff M.
Mercedes W123 DIY pages are now located here.
1983 / 1984 300D Sold
2000 CLK430 Cabriolet ~58k Sold
2005 Avalanche 4x4 ~66k

Well, the answer is simple anyway - my tire shop doesn't know anyone in the region who shaves. Seems to be a foreign or lost art!

I'm looking to upsize my rims anyhow - this just accelerates the process by a couple of years

Ken Silver
--------------
~1993 SL500, glistening black/grey on black leather, now in the shop for facelift painting lower body. After a week there it's getting more flat spots I guess!
~1991 Daimler, shiny grey on grey leather, best in country!
~1991 Miata MX5, sparkling BRG on tan leather, wife's - (and my polishing)
~1992 Honda US s/wagon, black/grey
ex 350SL, 230E, 280E (and a lot of other makes not nearly as nice)

my experience proves same as yours- shaving is a lost art- not many techs now are trained to do this

I've been told that the high perf tire category tires are less prone to flat spotting vs. the "max perf" category

-fad