Tire Pressure and tire life expectancy

[dwegmull]

My tires are at the default pressure from the day the car was delivered (a little over a year). Except for a four month "break" (car in shop following an accident), I drive it almost everyday and have accumulated over 6000 miles. I drive mostly on congested roads and suburban streets. I occasionally "put the pedal to the metal", mostly on highway on ramps. I do not race and rarely exceed 65MPH.
My rear tires still have about half of their thread left. By half, I mean the amount left above the wear bars is equal to the bars' own thickness. I will probably have them replaced at my next annual service, in December. The front ones are barely used. I guess they will last 50% to 100% longer than the rear.
I think driving on twisty roads has a significant impact on tire wear (added side stresses). The road surface on which you drive also impacts wear: a more abrasive surface such a rough concrete will claim more rubber than a softer asphalt. Of course, pot holes and other sharp impacts can't be good either!

[Nik]

My rear tires still have about half of their thread left. By half, I mean the amount left above the wear bars is equal to the bars' own thickness. I will probably have them replaced at my next annual service, in December. The front ones are barely used. I guess they will last 50% to 100% longer than the rear.
I think driving on twisty roads has a significant impact on tire wear (added side stresses). The road surface on which you drive also impacts wear: a more abrasive surface such a rough concrete will claim more rubber than a softer asphalt. Of course, pot holes and other sharp impacts can't be good either!

These tyre lives seem very short to me - does anyone know if US tyres are made much softer that European ones? On a variety of FWD ICE cars, I typically get 30,000+ miles from the front tyres and 60,000 from the rears. Manfacturer's recommended pressures usually more like 32-34 PSI, IME.

I don't have anything like the power of a roadster, and we don't have many concrete highways, but all the fuel savings from EVs are going to be spent on tyres if they don't last longer than that...

[Doug_G]

These tyre lives seem very short to me - does anyone know if US tyres are made much softer that European ones? On a variety of FWD ICE cars, I typically get 30,000+ miles from the front tyres and 60,000 from the rears. Manfacturer's recommended pressures usually more like 32-34 PSI, IME.

Roadster tires are made much softer than "European" ones, or North American ones for that matter, and probably get abused more. I get similar tire endurance on "ordinary" cars as you do.

[mpt]

I've found out that the car's tire sensors don't like pressures above 50psi for the rear tires. I'm guessing the front tires would be 40 psi maximum before the sensors give the warning.

Me too, I used to run the rears at 45 and found that on hot days the extra temp took them to 51 triggering a warning.

I'm assuming that the max pressure on the sidewall is the 'cold' pressure as, even at 40psi cold they can hit 46 at speed.

[mpt]

all the fuel savings from EVs are going to be spent on tyres if they don't last longer than that...

Yes, we figured that on the BBC fud thread, with factory tyres the cost of wear exceeds the cost of fuel!

[Nik]

I'm assuming that the max pressure on the sidewall is the 'cold' pressure as, even at 40psi cold they can hit 46 at speed.

Yes - if you have to drive to a garage to inflate your tyres you should never travel more than half a mile or so.

[Lloyd]

If you inflate with Nitrogen you will get much less variation with temperature. I keep a bottle for my cars and motorcycles.

[TEG]

Costco in the USA apparently uses nitrogen on tires you have installed there.
http://www.bargaineering.com/article...s-mileage.html
http://www.nitrofill.com/nitrogen-fi...ires-faqs.aspx

[Nik]

If you inflate with Nitrogen you will get much less variation with temperature. I keep a bottle for my cars and motorcycles.

Have you got any hard info on that? I know it's not exactly exhaustive research, but the top 10 hits on Google don't exactly fill me with confidence that there's a lot of benefit to be had.

[Doug_G]

If you inflate with Nitrogen you will get much less variation with temperature. I keep a bottle for my cars and motorcycles.

Variation with temperature - I really doubt it. Air is already 80% nitrogen.

The purported benefit of nitrogen is very slightly slower leakage, e.g. 1.5 PSI per year. Not a big deal, especially if you check your tires occasionally - or have a tire pressure monitoring system.