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Discussion Starter #1
Right now, I have new Nokians on the back and 7.5 year old Kumho Ecsta AST‘s on front, as I’m waiting for the new front Nokians to arrive. I reported that this combination felt great driving around the parking lot at low speeds, but once I got the car on the highway, I found out that above 40 mph, the whole front end shakes like a Maytag on spin cycle. The car also feels really darty, follows every groove in the road, and howls like it has a bad wheel bearing. So, my plan is to put new matching Nokians on the front, get the wheel alignment checked, and see how it drives. I hope I don’t need wheel bearings, ball joints, etc. to make it drive correctly.

BTW, the new Nokian‘s were made in Russia, first time I’ve seen tires made there. They claim to have “the new high modulus tread compound”, and silica added to increase tread life while maintaining great traction. Silica in tires I’ve heard of, but does anyone know if the other might be a reference to “modulus of elasticity” from high school physics? Is this just marketing, or does it actually mean anything significant?
 

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... reference to “modulus of elasticity” from high school physics?

... Is this just marketing...
I would like to know what high school you went to.

I would think so. Everyone has pretty much the same kinds of rubber to work with. Flubber was strictly fictional.
 

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What's your question here exactly? Yes, the car will feel significantly better with new tires on all 4 corners instead of 7.5 year old worn out ones on the front.
 

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It sounds like it is their attempt to make an "all season" tire handle better. It could be just marketing hype, but I guess you'll find out. Do you really need all season tires? They really are only meant for light snow. Good summer tires can be just as good in the rain, and sometimes better. No all-season tire will ever match the performance of good summer tires on dry roads.
Are you saying that before the new Nokians the car was fine on the highway above 40 ?
 

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Discussion Starter #5
What's your question here exactly? Yes, the car will feel significantly better with new tires on all 4 corners instead of 7.5 year old worn out ones on the front.
Two tire questions here, they can be identified by the question marks at the end.
“Silica in tires I’ve heard of, but does anyone know if the other might be a reference to “modulus of elasticity” from high school physics? Is this just marketing, or does it actually mean anything significant?”
 

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Discussion Starter #6
I would like to know what high school you went to.

I would think so. Everyone has pretty much the same kinds of rubber to work with. Flubber was strictly fictional.
In 1982, I graduated from to Tascosa High School in Amarillo Texas, and I took a year of physics there as college prep. It’s been almost 40 years, but as I recall, modulus of elasticity was a concept that we studied along with coefficients of friction and kinematics.
 

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Discussion Starter #7
It sounds like it is their attempt to make an "all season" tire handle better. It could be just marketing hype, but I guess you'll find out. Do you really need all season tires? They really are only meant for light snow. Good summer tires can be just as good in the rain, and sometimes better. No all-season tire will ever match the performance of good summer tires on dry roads.
Are you saying that before the new Nokians the car was fine on the highway above 40 ?
No, I just got the car running, and never tried to drive on the old Kumho back tires because they were too bald to pass inspection. The old Kumho fronts had enough tread to pass inspection, so I didn’t change them, but now wished I had, since at least one of them is obviously really bad.
 

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Discussion Starter #8
No, I don’t need all-season tires, it only snows every couple of years where I live. But I’m looking for that impossible combination of traits for the perfect tire:
1. great traction
2. long life.
3. Low cost
 

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That is a tough requirement. The only all-season tires that I know of will give you both long life and good traction are the Continental DWS. and they are not cheap. Good luck.
 

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Kumho Ecsta PS31 may be another option. They are 400TW summer tires. I live in South Texas so see occasional freezing weather, but not often. They grip pretty well in the wet too... Only time I have to take extreme care is if it's really cold AND wet, in which case I would usually just drive the other car. Dry grip is excellent. They are available in stock sizes. I've got 15k miles on my set and expect another 8k-10k before they're done.
 

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A high modulus compound means they are hard, so will wear well but won't have as much grip as a softer tire.

Low price, good grip and good life - pick only 2.
Very low price, great grip and great life - pick only 1.
 

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Discussion Starter #15
Yes, I came across this info on an Italian rubber company’s website. It looks like modulus is just the stress (force) required to produce a certain strain (deformation). And the harder the compoun, the higher the modulus.

MODULUS

Perhaps the best single gauge of a compound’s overall toughness and extrusion resistance, modulus is the force (stress) in pounds per square inch (psi) required to produce a certain elongation (strain). This elongation might be 50%, 100%, or even 300%, though 100% is the most widely used figure for testing and comparison purposes.

Industry literature typically refers to 100% elongation as "M100" (or modulus 100). Compounds with a higher modulus are more resilient and more resistant to extrusion. Generally speaking, the harder a compound, the higher its modulus. Because it is basically a measure of tensile strength at a particular elongation (rather than at rupture), modulus is also known as tensile modulus or tensile stress.
 

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Yokohama Advan Fleva V701 300 treadwear rating about $90-$100 per tire this is the replacement for the Yokohama S-Drive, available in Spyder sizes.
I've had these since late November but haven't driven much because of bad/cold weather. What little I have, they've been great.

Sent from my moto g(7) supra using Tapatalk
 

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Elastic modulus

An elastic modulus (also known as modulus of elasticity) is a quantity that measures an object or substance's resistance to being deformed elastically (i.e., non-permanently) when a stress is applied to it. The elastic modulus of an object is defined as the slope of its stress–strain curve in the elastic deformation region:[1] A stiffer material will have a higher elastic modulus.
I would submit that elastic modulus would measure a tire's resilience.
 

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Discussion Starter #19
Treadwear is a rating that doesn't actually mean anything anyway. The average 400tw will be fine for most Spyder owners, enough grip.
So, here’s what I’ve been able to piece together and I believe to be accurate:
Treadwear rating is a relatively arbitrary number assigned by the manufacturer, supposedly in comparison to a TW100 government standard tire. It is generally inversely related to grip, but not necessarily comparable between brands. A badly designed tire can have both low grip and low tread life, and a really well-executed tire can have both good grip and relatively long tread life. The traction rating is slightly better, but it only measures a tire’s kinetic (sliding) coefficient of friction in a straight line on wet asphalt and concrete surfaces. But, at least it’s determined independently and referenced to a definite scale.

Traction
Grades Asphalt g force Concrete g force
AA Above 0.54 0.41
A Above 0.47 0.35
B Above 0.38 0.26
C Less Than 0.38 0.26

So, we‘re mostly stuck with somewhat subjective tire tests and reviews, our own experiences and advice from other like-minded drivers. A few companies (tire rack for example) have test tracks and are set up to do repeatable, instrumented testing. They often do a good job, but it’s an expensive, time-consuming task with testing done on all types of tires, not just high-performance tires, so you may have to dig to find what you want. There’s also a bewildering array of tire categories to choose from. This from tire rack‘s website for test results, I assume in descending order of grip until you get to track/competition tires:

Passenger Tires
Extreme Performance Summer
Max Performance Summer
Ultra High Performance Summer
Ultra High Performance All-Season
High Performance Summer
High Performance All-Season
Performance All-Season
Grand Touring Summer
Grand Touring All-Season
Standard Touring All-Season
Passenger All-Season
Winter / Snow
Track & Competition DOT

So, for my bone stock 03, do I want an Extreme Performance Summer tire, or would an Ultra High Performance All-Season be the best tradeoff since it’s still apparently grippier than a High Performance Summer?

This is making my head hurt, so I’m going to stop bloviating now.
Anyone who’s read this to the end should surely be cured of their insomnia by now.
 

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Should have had this in my previous post:

Resilience Testing

Resilience of a rubber compound is a measurement of how elastic it is when exposed to various stresses. Measurement of a material’s resilience can assist engineers and scientists with choosing the right material for a given application.
Also I would like to caveat my previous comment that modulus of elasticity, or in the OP, the high modulus treading compound, "could" refer to tire resilience. In this case resilience would be the quantified tire's ability to return from deformation.
 
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