It's not just hard and soft compounds any more but rather the blends they use to make the rubber. Tyres with a fair whack of silicon or silicon polymers have the best of both worlds in both grip and service life. When I first got my bike the average life for a rear tyre was 3000km (careful riding) but this could be reduced to about 25 spirited laps of the local race track where the tyres ended up being melted into oblivion. Now I use silicon based hoops and get much more grip and about 10 - 13 K from a set of tyres. It was the same when I used to be involved in car racing. We used a bridgestone control tyre (soft and sticky) which would last 1 meeting (About 45 laps, $1400 ouch). The class then switched to a yokohama control tyre (high Si content) and the WRX was 1 sec a lap quicker with the tyres lasting more than half the season. These things are slicks with a few lines cut in them for light rain.
I remember seeing something on TV recently about silica tyres improving your fuel consumption
Quote
"Research has shown that the use of silica can reduce rolling resistance by up to 25 percent. Assuming correct tyre pressures are maintained, and making allowances for varying speeds and different driving characteristics, a 25 percent reduction in rolling resistance equates to around 4 percent fuel saving"
Hi Eric,
Here is something to guide you through all of the information on the sidewalls of your tyres. Trevor and Mark, Silica and Silicone are poles apart and it is the Silica (sand) that provides better wear and grip qualities in tyres.
Preserving the life of your tyres is as simple as regular monitoring of pressures and even tyre wear, running tyres a few PSI over factory recommended pressures will increase tyre life as the tyres run cooler, rotation every 10000klms is good practice as is checking treads for stones and other stuff.
Greg.
P.S. Ben, If the B/Stone Potenzas on my MX5 (RE 050A's) only return 26000klms, $360.00 per corner I will not be happy!
Hi Eric,
Here is something to guide you through all of the information on the sidewalls of your tyres. Trevor and Mark, Silica and Silicone are poles apart and it is the Silica (sand) that provides better wear and grip qualities in tyres.
Greg.
Thanks for that Greg, I have always been led to believe that silicon polymers were used to enhance the properties of the tyres (synthetic rubbers). Unfortunatley it is not possible to rotate tyre on a motorbike .
Seriously folks, you should not have tyres on your car that long. The tyre rubber is soft and pliable when new, but hardens and becomes brittle with age. This is accelerated by heat, UV exposure and other factors. Remember that the only thing between you and the road is a small patch of rubber.
The roadholding of these tyres would not be seriously impared around corners etc. as I doubt they had any in the first place. If you never push your car then that level of grip may suffice. I myself would not be happy and would simply throw them away. The area of concern is your braking distance. This will be probably tens of metres worse than when the tyres were new, that's about two car lengths, it means you not only hit the kid that runs out into the road, you probably kill them. All for the sake of a few hundred dollars, which you are eventually going to have to spend anyway.
Tyre manufacturers should not be able to make this rubbish, the stuff coming from China and Korea is bad, seriously bad. I wouldn't put them on a shopping trolley, let alone a 1.5t car capable of in excess of 110kmh. Wake up and take road safety seriously, yours and others. Buy good tyres and change the bloody things after 60,000kms or two years, MAXIMUM. Do you wife and kids ride in these cars with crap tyres on them? How would they feel to know that you're risking their lives to save a few hundred bucks, whilst spending money on telescopes?
Sorry for the rant, but this oneupmanship over how long your tyres lasts hits a raw nerve, particularly when a lot of the people espousing it (not necessarily here) are the "Speed Kills" nazis with little or no understanding of road safety.
I know quite a bit about heat cycles for tyres. For road tyres it really doesn't matter, UV and normal weathering degrades the actual rubber. For race tyres, yes the extreme heat generated during a race boils the plasticiser from the compound (which is what makes it soft), on my tyres they form a blue tinge on the outside edge of the tread. After a few heat cycles the tread starts to harden and the tyres take longer to warm up, once at operating temperature the work fine, but it is the first sign that they should be changed. I tried to get away with not changing a set of tyres for "one more meeting", combined with a cold day and a green track at Phillip Island...
Bugger, found a screw in my back tyre yesterday morning after loading up with a tonne of retaining wall blocks. I decided to just get them changed, so 95,000 on the original back tyres. Have to go commercial grade for the Hilux.
I think some of the numbers mean they were manufactured in the 30th week of 2008.
frank
Quote:
Originally Posted by erick
Ooops! I just checked my records - I got 125,000 km out of the previous set of Yokahamas - I have a long way to go yet to match that. We shall see.
BTW, the current set are covered in words and numbers. They are Yokohama A.drive, size 185/65R14 86H, Treadwear 300, 4U06 YYY 3008. Well that's some of the info on the tyre
Given I'm doing 50,000km a year at the moment, my tyres will wear to minimum tread long before they age.
I do remember when I was a poorly paid researcher with a big mortgage and a dependant family of five - the Sigma Wagon had to make do with radial retreads! Not nice times
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