I have noticed quite a few threads on PSI and what to inflate to. Best advice! Go by whats in your manual or on your door.

If you run a 17" then odds are the manual will tell you 38 PSI Under 100 mph and 41 PSI Over 100 mph.

The 16" is probably 33 PSI and 36 PSI.

I notice way to many people under inflating them due to the stiffness. The car is meant to be stiff for handling. Mini's actually have a messed up alignment from the factory. They have a decent amount of negative camber in that alignment for handling meaning if you look at your rear you'll notice your wheels lean in. They sacrifice tire life for handling. Most german (aka british) manufacturers do.

Running your tire pressure below what that placard says will cost you up to 30% of your tread life. Pumping them up helps the car wear more torward the middle as the tire leans in. This is why they call for a slightly higher PSI. That and weight. A lower profile tire such as a 17" or bigger also runs the risk of damaging a rim with a low PSI, in part why the pressure generally goes up. The bigger the rim the smaller the tire and less volume of air that goes in (keep the psi up).

The best trade off for comfort and handling is to ditch the run flats. The run flat has a stiff sidewall. For those of you with a 16" wheel (195/55 R16). Going to 17" 205/45 R17) non run flat is probably the best trade off available to you. Bigger wheel, looks nicer. That run flat on the 16" will be stiffer than the low profile tire you get and the cost of tires are about the same these days on a 17" vs 16" wheel. That and you wont get the tire roll on the 17" with a non run flat as you probably would with a 16" non run flat.

We all know Mini's eat tires since they are set up like little track cars. The reason being is because the tires lean in naturally since the alignment is set up to give you better handling at the sacrifice of tire life. The vehicle calls for 38 PSI on a 17" for this reason, to try to balance it out and make the tire last a little longer. Run the recommended specifications. A bonus will be slightly better MPG. But more importantly your tires will last longer and the odds of feathering a tire up on the inside will be reduced (in which these cars love to do).

Also rotate them every 5k - 10k (sooner is probably better but may be a pain for some) and don't expect 50k out of a set of tires because of this. Most tire manufacture warranty's are based on a more common car that has a pretty straight forward alignment and tread wear ratings are based on their top of the line, not a competitors or gov. standard. There is no regulation in those numbers. Example: Continental with a Tread Wear Rating of 400 and Falken with a Treadware Rating of 500. On paper it looks like the Falken will last longer but those numbers are based on that specific manufacturers top of the line. If Falkens top of the line is crap it'll wear out faster than the continental with the lower rating and Falken is known to do this as they make their compound sticky and sacrifice tread life to give you performance at a low cost.

For the 17" I have been running a Cooper Zeon RS3-A Ultra High Performance All Season. I'm not going to say its your best option but for me in the midwest I like the tire and they are priced reasonably well for what you get but Continental and Bridgestone have some excellent options as well.

***This mainly goes for the S or JCW but applies to all models since tires options are the same. The S and JCW have the Sport Suspension etc.

This is more information than I originally intended to give you. The short story is go by the PSI on your door sticker if its to harsh of a ride and you have a run flat ditch it and consider the rim upgrade to 17" if you have a 16" to retain its handling (18" is about the max for a wheel on these cars. Mini does have factory information on that size but the cost of the tires will go way up and odds of a bent rim too). The 17" seems to be the best overall balance. If you keep things simple and ditch a run flat on a 16" for a non run flat 16" do realize that because the sidewall is stiff on a run flat that car wont handle 100% the way it did before. In part why I'd consider the 17" for a non run flat as it will handle about the same as 16" with a run flat (run flats have a hidden benefit because the side wall is so stiff they give you an increase in handling reducing tire roll, you can compensate with non run flat tires going up a size as the sidewall will be reduced).

-I wanted to chime in and give you guys some feedback. For those of you running the lower pressures I hope your considering what I'm telling you. A GM product will zero most things out on an alignment. The Mini, Porsche, BMW sacrifice tire life to make the car handle. The higher than normal tire pressure is there to help reduce it. Consider that.

 

I autocross starting at 33 and I let them climb to 38 I dont like how re71-r feel over 38psi

I wish I could get camber on the front, I'm destroying my tires, the outside edge gets worn down to cords tooooo fast

My track car has camber plates, some negative camber sure helps a lot!

 

My (sig) MCS acquired 3 months ago came OEM equipped with 17" (silver) Conical wheels in combo with Conti Sport runflats. While I've considered switching to non-runflats, those tires looked nearly new with 17k miles on the car at time I bought it. I've been watching CL ads for OEM 17" JCW wheels to sharpen the aesthetic appeal (to my eyes) in contrast to fairly conservative White-Silver/White color scheme. I'm not willing to pay prox $1100 for new wheels, so seems I might just keep what I have.

Spotted a CL ad last weekend for GY Eagle Sport AS tires stated as having < 11k miles, removed from an MCS just before returned at end of 3-year lease. The wheels shown in the ad were "Conical" but car color wasn't shown. I wondered if a coincidence, so wrote the seller asking about the MINI they were removed from. Yep, very same car I bought, thus reason those runflats looked relatively new - only prox 6k total miles on them since 2013! Yep, I'm buying those GY tires and will have them in a few days. As noted, I'll continue inflating to 38psi...

 

RE71 is a good tire. Then Blizzaks for winter lol. Yeah Negative camber is what I ment. There's enough to shorten the life for sure. But in part how they handle.

 

The JCW LA Rally Challenge Spoke Wheel. I think that's what it's called. It was offered 09 - 14 and was on the JCW Challenge Car. Awesome wheel made in 17"S and 18"S and it's made by BORBET (Stock Option).

 

The JCW LA Rally Challenge Spoke Wheel. I think that's what it's called. It was offered 09 - 14 and was on the JCW Challenge Car. Awesome wheel made in 17"S and 18"S and it's made by BORBET (Stock Option). I have them. Love them but many spokes so hard to clean. I got mine with out tires for $350 but yeah well over a 1k without tires from the dealer. Keep your eyes peeled lots of ppl swap and dump the old parts.

 

Kristopher, how do you feel about running tires slightly over inflated? Talking about the R55 and R56 daily driver with spirited driving, or any other scenario you care to talk about.

 

Mini has tire pressures for over 100MPH which are typically 3lbs more than the listed or recommended. So going slightly over shouldn't affect much. On a 17" wheel it's 38 and 41. 38 for every day. Going to 39 or 40 will make it stiffer but by time in between air pressure loss. I wouldn't go too much more than what is recommended. The nice thing about Mini is there are so many configurations and quite a few tracked the manufacturer has definitely figured the car out. In the winter your tire pressure will drop faster with cold air. In the summer itll retain better. But over inflating in winter could cause traction loss etc. A pound or 2 should be okay though.

 

I aim for 40PSI hot with my Extreme Performance tires. Cold pressure don't mean much to me as I could be pushing harder on a road like The Dragon and the hot pressure (especially the front tires) are much higher than if I were driving on the highway. Just about finished with a set of Falken RT615Ks and will get ~15k out of them by inflating the tires to mid 40s while hot for highway runs and then 40PSI hot when doing twisties. Next will be the Nexen SUR4s. My buddies with the Conti ExtremeContact DWs run 40PSI hot as well.

 

All tires and wheel combos are different. Even within the same tire model changes in rim and aspect ratio can change the best pressure for a tire. You need to check wear patterns if you start getting wear in the middle its too much pressure if its on the outside probably too little. Alignment settings also can change the pressures and wear patterns you also need to rotate I rotate same side front to back. Most tires I run dont like going reverse. Higher pressures are great for dialing in but you need to learn about slip angles. Loads can also affect the pressure. Tires are really super complicated the best design models are cutting edge AI stuff and its still just a guide for testing

 

100% Agreed. You need to watch. Also when the temperature drops you will loose pressure. I check my pressures and wear about once every two weeks to once a month. I don't mind running 36 in the winter but I in fall I aim for 38 as I know I'll loose the 2lbs when the temperature drops maybe more given the time. Going into spring usually inflate to 36-37 knowing it may go up. 38 psi so far for me seems about right on average. But different rim and tire combos may call for more or less. The dealer seems to like 36 for everything but that probably has to do with the fact its easy for them to remember and on average most combos will run okay with that number.

 

I've become a TPMS junkie, which is the lazy man's replacement for jumping out at 80+ mph and trying to use the Longacre guage.

I've been surprised.

Over the last decade of autocrossing I've used the Longacre a lot, and learned how to manage pressure changes due to weather and run frequency, but never thought much about the day to day.

My observations in the last few months have been in the broad range of 40 degrees up to 80 degrees, and from initial roll in the morning to ghosting down 128 in the fast lane in the peak heat of a summer day.

Minimum pressure observed at 40 degrees Fahrenheit (coldish morning) and first roll was 33 psi, and max pressure observed was 42 psi at 80 over degrees on the Mass Pike (going quickly). A delta of an astonishing 9 pounds across the full range of speed and temperature.

And that's on the front axle when it wore the RE-71 sticky tires, with a initial inflation pressure of 35 psi done on a day when temperature was in the high 50 degree range.

I'm running the winter Continentals now on the OEM 16 inch rims, and have set them at 33 psi at 40 degrees. Again, conditions are cooler now and ambient temp seems to matter more than speed in raising the internal pressure, so to date my max observed pressure has been 37 psi. The delta is therefore a much smaller 4 psi, but the temp range is narrower as I said.

Anyway, I just had no idea that a 20% swing in tire pressure was a normal daily occurrence!

Cheers,

Charlie

 

I am running sparco's in a 17x7.5 with 215/45 r17 with no clearance issues.