Tread wear

[RWLott]

I replaced the rear tires after 12,000 miles - the tires were worn in the middle, but still had tread remaining towards the outsides.

I decided to use 27 lbs. pressure on the new set (rather than the recommended 28) in an attempt at evening out the way the tread wore. After 13,000 more miles, the wear pattern has been the same - no tread left in the middle. I plan to try 26 lbs. pressure on the next set.

So far the front tires are wearing evenly and have plenty of tread left while running 28 lbs. in them.

Any thoughts on tire pressure VS tread wear?

[Mr. Know]

Helps to specify which tires you are speaking of.

[RWLott]

Originally Posted by Mr. Know

Helps to specify which tires you are speaking of.

I went with Goodyears from Tire Rack: Eagle F1 245/40ZR17 91Y

I like them and plan to use them again.

[khamai]

Originally Posted by RWLott

I replaced the rear tires after 12,000 miles - the tires were worn in the middle, but still had tread remaining towards the outsides.

I decided to use 27 lbs. pressure on the new set (rather than the recommended 28) in an attempt at evening out the way the tread wore. After 13,000 more miles, the wear pattern has been the same - no tread left in the middle. I plan to try 26 lbs. pressure on the next set.

So far the front tires are wearing evenly and have plenty of tread left while running 28 lbs. in them.

Any thoughts on tire pressure VS tread wear?

Stay with recommended or close to recommend tire pressures and have the alignment checked in the rear, specifically toe-in.

At best I was getting 5-6Kmiles on my 048s with the centers completely gone. Post alignment, removed a lot of toe and now just a hint of toe-in, I'm at 4Kmiles and more even wear.

Center tire wear is a symptom of too-much toe-in.

Keep in mind the general rule is high tire pressure = center wear, but the OEM Goodyear tire on late 80's Esprit would wear in the center (rears) when the tire pressure was too low. Why? Because the construction of the tire allowed the center of the tread to bow outward (centripedal force) at speed.

So, check out the alignment at the rear. Of course the other solution is drive harder and start drifting around the corners to wear the outside of the rears!

Cheers,
Kiyoshi

[RWLott]

Originally Posted by khamai

Stay with recommended or close to recommend tire pressures and have the alignment checked in the rear, specifically toe-in.

At best I was getting 5-6Kmiles on my 048s with the centers completely gone. Post alignment, removed a lot of toe and now just a hint of toe-in, I'm at 4Kmiles and more even wear.

Center tire wear is a symptom of too-much toe-in.

Keep in mind the general rule is high tire pressure = center wear, but the OEM Goodyear tire on late 80's Esprit would wear in the center (rears) when the tire pressure was too low. Why? Because the construction of the tire allowed the center of the tread to bow outward (centripedal force) at speed.

So, check out the alignment at the rear. Of course the other solution is drive harder and start drifting around the corners to wear the outside of the rears!

Cheers,
Kiyoshi

Thanks.

When I have the new set installed at the dealer, I'll have the toe-in checked.

Had not thought of having the centers wear due to driving at speed - many of the miles are at expressway speeds. The difference in wear pattern compared to the fronts (they appear they may have another 25,000 left in them) is puzzling?

[khamai]

Originally Posted by RWLott

Thanks.

When I have the new set installed at the dealer, I'll have the toe-in checked.

Had not thought of having the centers wear due to driving at speed - many of the miles are at expressway speeds. The difference in wear pattern compared to the fronts (they appear they may have another 25,000 left in them) is puzzling?

Actually not too puzzling... Consider that the fronts carry half the weight and aren't propelling the car.

Consider how much faster you wear out the fronts on a FWD vehicle, thus the tire rotation to even things out. Of course there's no tire rotation (front to rear) on an Elise/Exige.

I've replaced my fronts every other time I replace the rears.

Cheers,
Kiyoshi

[RWLott]

Another explanation/possibility I heard recently for the tires wearing out in the middle while there is still plenty of tread left at the edges has to do with the extra width of the tires. The centrifugal force on wide tires at speed might make the centers bulge out more. At lower speeds an evenly distributed contact patch should be easier to maintain.

If centrifugal force is the reason, I'm thinking it probably does not matter what pressure is used, so I'll probably revert back to the manual recommendation of 28 lbs in the rear.

I did manage to get close to 15,000 miles on the current rear set of Goodyears - 245/40ZR-17 Goodyear Eagle F1 GS-D3.

[lotusfan2]

Others run those same Goodyears, including myself, at 3psi higher than stock pressure, to compensate for the less stiffer sidewall of the Goodyears as compared to the A07/A048s. I just measured my Goodyears, and after 4000 miles they are slightly more worn on the outside than the middle. In the front the difference in wear is 1mm, in the back 0.5mm. Given this, I think I'm going to try 2psi over stock, thus 28 in front and 30 in the rear.

[RWLott]

Originally Posted by lotusfan2

Others run those same Goodyears, including myself, at 3psi higher than stock pressure, to compensate for the less stiffer sidewall of the Goodyears as compared to the A07/A048s. I just measured my Goodyears, and after 4000 miles they are slightly more worn on the outside than the middle. In the front the difference in wear is 1mm, in the back 0.5mm. Given this, I think I'm going to try 2psi over stock, thus 28 in front and 30 in the rear.

Thanks. I'll give 30 lbs a try. I have close to 27,000 on the car.

[lotusfan2]

How far down were the rear tires for you after 12,000 miles? I'm at 4000 miles on my Goodyears, and down to half thread from new. Those tires are not going to make 12,000 miles for sure. No track miles, but I do drive "assertive". Lets call it that

[RWLott]

Originally Posted by lotusfan2

How far down were the rear tires for you after 12,000 miles? I'm at 4000 miles on my Goodyears, and down to half thread from new. Those tires are not going to make 12,000 miles for sure. No track miles, but I do drive "assertive". Lets call it that

The rear tires have 2.5 mm (right rear) to 3.5 mm (left rear) of tread left on the outsides of the tires. There is no tread left in the centers.

The original tires were replaced after 12,100 miles - very little tread left in the centers. There is currently 27,040 on the odometer, so after 15,000 miles I'll be replacing the current set of Goodyears tomorrow.

I probably drive similarly. I've done a few laps at the Beaver Run track in PA, just fast enough to feel the tires creep a bit on some of the turns. Just returned from a trip to the Tail of the Dragon (1500+ miles, about 300 of those miles locally with 10 runs on the 11 mile Dragon plus the 9 additional miles from Deal's Gap to the Fontanna Lodge).

[lotusfan2]

Interesting! Mine have 4mm (outside) to 4.5mm (center) left on the rear, after about 4000 miles.

[Zoomer602]

This is unrelated to the thread but posted elsewhere without reply yet so I am repeating here - as I need to buy tires today to get an inspection sticker:

How does one buy 4 tires for a Lotus Esprit (1999). My stock tire sizes are 285/35/18 in the rear and 235/40/17 in the front. If you are suppose to match tread and tires it seems almost impossible to do with the tires I am trying to compare. Nitto 555 has the rears but not the front size. Michelin's (can get 1/2 in Sport ps2 and 1/2 in Sport, Goodyear (F1 GS-D3), General Exclaim UHP - NONE of these have 4 tires that I can buy with matching tread patterns. Tirerack only shows two choices for the car with matching tires....SO....how do others deal with this?

[RWLott]

Originally Posted by lotusfan2

Interesting! Mine have 4mm (outside) to 4.5mm (center) left on the rear, after about 4000 miles.

The new ones are starting out with 8.7+ mm of tread. I'm hoping to get better even wear with 30 lbs.

[lotusfan2]

Originally Posted by Zoomer602

This is unrelated to the thread but posted elsewhere without reply yet so I am repeating here - as I need to buy tires today to get an inspection sticker:

How does one buy 4 tires for a Lotus Esprit (1999). My stock tire sizes are 285/35/18 in the rear and 235/40/17 in the front. If you are suppose to match tread and tires it seems almost impossible to do with the tires I am trying to compare. Nitto 555 has the rears but not the front size. Michelin's (can get 1/2 in Sport ps2 and 1/2 in Sport, Goodyear (F1 GS-D3), General Exclaim UHP - NONE of these have 4 tires that I can buy with matching tread patterns. Tirerack only shows two choices for the car with matching tires....SO....how do others deal with this?

Zoomer, you might be able to get slightly different sizes that do make up a complete set. Maybe go a little wider (or less) on the front or back. Use the tire size calculator to keep your diameter close to what you have now.

Tire size calculator

Call Tirerack (Tire Rack - Your performance experts for tires and wheels) and ask them. They are very knowledgeable. Maybe they can help.

[Zoomer602]

I think I may just go with the Nitto 05 . Not thrilled with the 05 but they do come in the correct sizes and are reasonably priced. Probably will wear quickly if I am not happy anyway...Anyone use the 05?

[lotusbrakes]

Originally Posted by Zoomer602

I think I may just go with the Nitto 05 . Not thrilled with the 05 but they do come in the correct sizes and are reasonably priced. Probably will wear quickly if I am not happy anyway...Anyone use the 05?

How wide is the rear rims?

-G