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[ehagerty]

All,
I went to air up the tires on my 128 w/sport pkg due to the low tire pressure notification and am curious which of the two recommended pressures I should adhere to. It lists 2 on the door jam and an explanation in the manual which I understand but just am curious what you all found to be a happy medium. It has stock P-Zero run flats installed.

32/35 f/r
(full car, full car with luggage up to 100mph)

35/42 f/r
(full car over 100mph without luggage)

I would tend to say 32/35 f/r but the dealer had way more than that in it originally.

Thanks for the feedback.......

[rking117]

you can get away with the lower number if you are not runing higher speeds. However you can go inbetween the two numbers if you travel at higher speeds. just if you get over 100mph i would use the high tire pressure but understand your tire wear will be different and faster.

[bmw1racer]

Remember to reset your TPMS after airing up.

[1speedbike]

If you have a lower tire pressure, more of the tire is in contact with the ground. At higher speeds this could cause a lot of friction and therefore a lot of heat to build up in the tires, which can cause them to fail. Also your treadwear is gonna go to shit. I think that's why they recommend running higher pressures when driving faster. If you don't spend an appreciable bulk of your tire over 100 MPH, like on an autobahn, then you don't need to worry, as not enough heat will build up in the relatively shorter amount of time. If you spend a decent amount of time on a highway that will allow for 100 MPH or over, you can set them somewhere in between to be safer. I don't think tire pressures that high are good for highway driving. I've driven on snow tires at 100 MPH at about 38/38 and had no problems (though for the 135i the recommended pressure is 36/36).

[ehagerty]

Thanks.....no autobahn in Charlotte. Just wanted to make sure there was not something i was missing