[Jeffbezos]

Hi, so I have 225/45RF18 91W and 255/40 R18 95Y. I put in 35psi in the rear and 34psi in the front. I have no clue on how to read the sticker.
Can someone please help me?

[nurgburgring]

the big squares is the tire profile and the small squares are tire pressure, like 2.2 and 2.4 is bar pressure. The ppl is your load. I ride 3.0 bar all around, u get better gas mileage and stability with higher pressure, with to low pressure the tire can worn in middle. Try to put 2.7bar/39-40psi.

[Ragnar The Redneck]

Originally Posted by nurgburgring

the big squares is the tire profile and the small squares are tire pressure, like 2.2 and 2.4 is bar pressure. The ppl is your load. I ride 3.0 bar all around, u get better gas mileage and stability with higher pressure, with to low pressure the tire can worn in middle. Try to put 2.7bar/39-40psi.

Higher pressure will wear in the center more, while lower pressure will wear the outside more.

[nurgburgring]

Originally Posted by Ragnar The Redneck

Higher pressure will wear in the center more, while lower pressure will wear the outside more.

yeah thats true, my bad

[thejeremyman9]

3 bar is quite high... 34-35 psi is reasonable. Depends on what you want. It's somewhat up to you, within reason. I run 32F/35R on 19s. As long as you arent under 30 psi you can adjust to your liking really, just watch wear patterns.

[Onizukachan]

I run 34f/39r on square 18s, helps dial out the remaining under steer.

[b58huncho]

35 psi would be your optimal air pressure for that size and vehicle

[Onizukachan]

Originally Posted by b58huncho

35 psi would be your optimal air pressure for that size and vehicle

Disagree, as does BMW.

What do you base your opinion on?

[Ennoch]

On a 335XD F31 I run 2.7 bar all round on both Sottozero RFT winters and PS4S non-RFT summers and find it gives a good blend of handling and wear. The higher pressures keep the steering sharp and help balance central tread wear with edge wear from hard driving. That said I do drive the car quite hard and get it rotating which prevents the usual outer front edge/inner rear edge wear that BMW's suffer from a lot.

[rdt22]

In Germany, two times now the shop inflated them all to 2.7

The wheels before(original runflats) had inside wear, probably because of the 2.2 air pressure in them.

[B58-Hustler]

To read the sticker:
Step 1: find your tire size in the left column
Step 2: decide what your load is (top section is for 3 or fewer people, bottom section is for a full car and some luggage)
Step 3: pick front or rear column
Step 4: use the pressure based on the load and location
Step 5: repeat for the rear tires

This picture shows how you'd get to your appropriate front pressures. If you generally ride light, it's 220 kPA or 32 psi. If you ride heavy, it's 260 kPa or 38 psi.

For the rear it's a bit blurry but I would say it's suggesting 220 kPa or 32 psi for light load, 270 kPa or 39 psi for heavy.

Personally I would aim for the middle ground as you have and I'd go with probably 35 in the front and back. Keep an eye on wear and adjust here and there as needed.