Hard Tires--Durometer reading

NO KIDZ

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I see a lot of talk here about about hard tires and the problems
they cause. And I understand checking the codes for the manufacture date. What I would like to know what the Durometer reading would be for a hard tire. I have runflats on my 98 GTS that are 3 years old and I have not had any problems with handling or traction. But if someone had some hard data numbers , I could just check my tires. For me, this would make more sense than using a SWAG method and buying new tires just because yours are a couple years old. I was just bored and wondered if anyone had thought of this.If this has been covered I apologize, I did not find it when I did a search
 

sdaddy

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I have 8 year old Pilot Sports on one of my Vipers and they seem fine. Is a wide variation in temperature extremes harder on a tire than a constant warm climate. My car has bever been out of Florida and the tires never see extreme cold or extreme heat (as compared to Arizona) or low humidity.
 

Viper X

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Tires soften and harden with temperature, so be aware of that when comparing durometer readings.

sdaddy,

If you have 8 year old Pilots, they are dead, should be removed and burried (figuratively speaking) regardless of mileage. They will let go on you one day without much if any notice and you will then be along for the ride.

As a VCA Prez, I regularly get calls from owners asking where they can take their cars for body work. I always ask them what happened and most of the time, the problem is old, hard rear tires. Driver error, usually due to inexperience handling Viper (no track time), is the second most popular method of crashing a Viper out here.

Good luck,

Dan
 

Leslie

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I have 8 year old Pilot Sports on one of my Vipers and they seem fine. Is a wide variation in temperature extremes harder on a tire than a constant warm climate. My car has bever been out of Florida and the tires never see extreme cold or extreme heat (as compared to Arizona) or low humidity.

omg, what ViperX just said, pleazzze ditch those tires! That's serious business, I would head straight to the tire store and take your wheels in to be mounted then take them home to your Viper.

Had a guy at the track last month with PS tires, lots of tread on them, they looked almost NEW. We went out for our session, I was right behind him and saw the tires out of NOWHERE just loose grip and .....off the track he went.
 

FastZilla

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Using my Long Acre Durometer:

75 - Old PS Cups (rear with 5800 miles over 7 months & 6+ hours of track time)

68 - New PS Cups (rear with 2 hours of track time ~100 miles)

86 - Rear old slick PS 1's on RT - no idea how old they are.

Enough of a difference to say the PS1's are 30% harder. I plan on turning my PS1's into a smokey Youtube video. Gonna throw the old PSC's on the back of the RT as ghetto "drag radials"...

For reference:
76 - Jeep Goodyear Eagle RS-A (Run-flat, rear, 11 months old & 27k miles)
68 - Jeep Goodyear Eagle RS-A (Run-flat, rear, 6 days old & 1k miles)

80 - Dodge Ram 2500 Michelin "E" rated truck tire (21k miles & 8 months old)

Conclusion:
60's - good soft (track) tires
70's - Hard track tires and good street tires
80's - good truck tires & dangerous Pilot Sport tires
90's - Solid rubber hand-truck tires

Maybe this helps...
 

Warfang

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Tires soften and harden with temperature, so be aware of that when comparing durometer readings.

sdaddy,

If you have 8 year old Pilots, they are dead, should be removed and burried (figuratively speaking) regardless of mileage. They will let go on you one day without much if any notice and you will then be along for the ride.

As a VCA Prez, I regularly get calls from owners asking where they can take their cars for body work. I always ask them what happened and most of the time, the problem is old, hard rear tires. Driver error, usually due to inexperience handling Viper (no track time), is the second most popular method of crashing a Viper out here.

Good luck,

Dan
While I'm pretty sure old tires are bad news... the conclusion drawn is not really scientific. These are all anecdotal evidence. How do we know #1 cause isn't really #2? It's easier for a Viper owner with an ego to blame the tires than his inability to handle the power.

Here's an interesting read:
Tire Tech Information - Tire Aging – Part #1

"BRMA(British Rubber Manufacturers Association) members strongly recommend that unused tyres should not be put into service if they are over six years old and that all tyres should be replaced ten years from the date of their manufacture."

and...
"Several European vehicle manufacturers of high performance sports cars, coupes and sedans identify that "under no circumstances should tires older than 6 years be used" in their vehicle owner's manual. However, it should be noted that European recommendations must include driving conditions that include roads like the German Autobahn, which allows vehicles to be legally driven at their top speeds for extended periods of time."
 

Kala

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Hey Fang!

Down here in So Cal... The saying is "In Dan we trust"
Dude knows his stuff...

Take a ride around Willow Springs with him... :2tu:
You'll get a tire education you never thought possible :lmao:
 

plumcrazy

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can this be copied to the tire section for luke at tire rack to get involved maybe ?
 

Tom F&L GoR

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Fastzilla is on a nice track by collecting data. I'd be very interested in measurements after the tire warms up. We all say "cold tires" or that the slicks need to be heated...so what is the durometer reading when they are "warmed up"?

Also, the durometer measures the rubber deflection, which is perhaps still one step away from what we want to know - tire friction.
 

ViperGTS

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If you feel (with your hand) how sticky a new and warmed up (hot) tire is
compared to
the lukewarm old tire...you know the difference!
 

Chuck 98 RT/10

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You drive to the limits of your tire. It doesn't matter if you're on brand new Hoosiers or Fred Flinstone rocks. But you better find those limits before you put your foot down. If you're driving beyond the limits of the tire don't blame the tire for being too hard or old.

sdaddy must not drive his Viper much if he still has tread after eight years. I've never been able to keep a tire for eight years. Seems to me they are down to the wear bar at around 35,000 (fronts) and every time they start getting near that they start developing a vibration. I don't even have to check the tire anymore.
 
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NO KIDZ

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Thanks for all the good info. My tires check around 78 on my durometer, so I guess it is time to start looking for a new set of tires. I guess I will get tires instead of a new exhaust.
 

RoadiJeff

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I guess it is time to start looking for a new set of tires. I guess I will get tires instead of a new exhaust.

If you decide to go with Michelin they are currently running a Friends of Michelin rebate through October 31. It's good for $60 back on a set of Michelin tires. It does not matter which retailer you purchased them from.

I received my rebate check a few weeks ago. You may have to call them back and haggle before they send it out. I originally received a letter saying my rebate application was denied because the tires I purchased were not part of the promotion. Since the tires I bought were not on the excluded list I called and asked why. They said that the invoice copy I sent them did not show what model tires I bought (it did). Anyway, they mailed me the check after a brief discussion.

The number to call for this NON-VISA rebate (Friends of Michelin) is 1-866-866-6605.

I replaced my 1998 DOT code original tires a few months ago with PS2 tires from JonB at PartsRack. With a little over 19,000 miles on them the tread still looked like they could go another 10,000 miles or 5 years, whichever came first. The new tires certainly made a difference in tracking and overall driving.
 
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