Tire question, slight cracking between the tread blocks.

[Kouki monster]

Hey Guys,
Quick question, I have a set of Toyo R1R's that were stored in my garage. I was going to mount them this week for a track day but when I looked them over they have small cracks in between the tread blocks? Tires have lots of meat left on them but are 3 years old. No cracking anywhere else side walls are perfect etc.
Thanks for any info.
John

[Astraist]

The tire rubber has aged and degraded. I recommend not using it. I personally wouldn't even use such a tire on my street car for street driving purpose!

When I was first tuitioned at advanced/performance driving, three years of age were described as the point from which tires (road tires for normal driving use!) are to be put out of service! The tires suffer from wear which is a result of aging. Tire aging is a result of oxygen and ozon, sunrays and UV; moist, salt and pollution in the air, as well as temperature changes over the day and year, etc. The effect is similar to what a tire experiences after it has passed through the maximum amount of "heat cycles" it can endure during a race: The tire is not externally worn, but is rather dry on the tread (especially in the corners) and it's hystersis is also lacking.

Eventually, the rubber dries out and degrades, essentially it turns into plastic, and loses up to 50% of it's abilities! The effects are increased when the tire is not moving and with soft-rubber compounds, as in your case. At an experiment we did, we found serious degrading in tires as young as a mere two years of age. Of course the Israeli sun is probably more harsh on tires, I presume. I've seen such cracks develop into a rupture of the tread or a blow-out, and that's on highways. I'd hate to think about what it would cause to a race-purpose tire!

[JimLill]

Originally Posted by Astraist

Of course the Israeli sun is probably more harsh on tires, I presume.

Many people assume that being closer to the equator or in some desert climate is the harshest sun. While it is one of the harshest, the more sun and UV damage, within a single season, can occur at more extreme latitudes where the solar day is longer.

[Kouki monster]

Not sure if they are bad enough to scrap. Seems to be a common problem. From what I could read(tire rack) they warn against side wall cracks which is a given.

[Astraist]

Originally Posted by JimLill

Many people assume that being closer to the equator or in some desert climate is the harshest sun. While it is one of the harshest, the more sun and UV damage, within a single season, can occur at more extreme latitudes where the solar day is longer.

Desert climate? why, is that the way you picture me? A head-veiled semi-nomad who is racing camels that run on diet petrol?

The big cities of my country are not as hot, but suffer from humid and salty air (courtesy of the Mediterranean ) and the same occurs around the Galilee. It's also worth mentioning that ozone oxygen is formed more prominently around electrical equipment. I just felt my first post had too much information already...

[JimLill]

Originally Posted by Astraist

Desert climate? why, is that the way you picture me? A head-veiled semi-nomad who is racing camels that run on diet petrol?

Mine was a general comment. I've been in your area, all over north Africa, and the east end of the Med. I have also been all over the rest of the world, including essentially every desert except the Gobi. I am currently sweltering in intense sun and heat here in Western NY and I have a pile of weather checked tires.

[Astraist]

You do realise I was just joking, right?

[JimLill]

Originally Posted by Astraist

You do realise I was just joking, right?

With you, we never know..........

[kbrew8991]

the was the give away

[JimLill]

Originally Posted by kbrew8991

the was the give away

I knew that....... my comment was aimed more at his whole post. IMO, he sometimes portrays situations such that he may think we here in the new world live in a shell.