Correct tire pressure?

[rei00]

According to page 81 of U.S. owner's manual, correct pressure for Cooper S is from 30 to 41.

What does M+S mean? I can't find it anywhere in the manual. How much pressure are you running? I checked mine, and it showed 31 psi. Should I increase it to 35 since I get 2 extra passengers from time to time?

[HarryHBMCC]

The tire placard shows the proper pressures. The tire sidewall shows the maximum the tire can take.

M+S is a designation for all-season tires. If your tires are not all-season (ie. if you got the sport package) then you won't see M+S because they aren't "mud and snow" rated so use the ratings for the H speed rated non-M+S tires. If you get Q rated snow tires, use the numbers for M+S Q rated tires on the placard instead of the H rated M+S numbers.

How often do you drive fully loaded? If it is once a month to take people to lunch, you can leave it at 31PSI -- if it is often you may want to raise it but you may find the ride harsh at 35PSI when just 'your little old self' is in the car. If you are really keen you can keep a compressor in the boot (if you have the MINI mobility kit, it comes with one) along with a pressure gauge and then when you take people out to lunch you can say, "hey, just give me 5 minutes to pump up my tires."

I have a pressure gauge and compressor in the boot of my car anyways just in case I feel they are low. My MINI Cooper has performance runflats so it didn't come with the mobility kit but the space for it (or the jack if you have a spare) is still available in the Cooper and my compressor fits perfectly there under the carpet along with a litre of Castrol Syntec 5W-30 for when I need it (approaching 7000km it is now 3/4 of the way down to MIN). In your S, that space is, I think, taken up by the battery but there is still space in the trunk for it. I have some cleaning products and paper towels in there all the time to check the oil and to make it look good when I want to impress someone

Harry

[RickB]

My car was delivered with 35psi in the Pirelli Euforia (I love that name) runflats. After looking at the placard, I pumped them up to 38. I think I'll drop them back down to 35 or even 33, as I'm usually the only one in the car, and a slightly better ride would bring me more smiles than the couple of occasions when the extra air would improve the handling.

[minirossa]

Check out tirerack.com I bought some tires for a GTI
a few years ago & they included a brochure on tire care.

Basically their advice on tire pressure is this:
The car manufacturer recommends the tire pressure that will give you the best ride (30-33psi on my Cooper's 16" Goodyears). The tire company recommends the pressure that will make the tire wear last a long as possible (51psi says Goodyear). So I split the difference at 40psi.

One can use this as a guideline & "tune" the pressure
to suit your driving. Cornering, city-vs-highway and how
hard you drive are all factors.

My tires were at 35psi upon delivery & the ride is harder
at 40psi. However the car seems to corner better.

Try it out!