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Hi all. When. I first got my 528 I had the dealer put nitrogen in the tires. For the last year it's been great.

Today I got a warning that One tire was low. I reset the pressure and it's still showing as low.

It's Sunday. Do I top the tire off with regular air until I get to the dealer ?

I don't think any service stations by me have nitrogen

Thanks in advance
 

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Forgot to ask. Would a normal tire repair place be able to patch a run flat?
Yes. The bmw dealer would probably not, and just want you to buy a new tire. As long as the hole is more than an inch from the tire edge, should only cost about $25.
 

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You want to find a place with a lever-less tire machine. This will prevent the rim from getting scratched up during the removal of the tire from the rim. These machines are relatively new and relatively expensive. So, don't expect Midas, etc. to have them. Your best bet is a high-end new car dealership (BMW, M-B, Porsche, etc.). You also want to have them use a high-speed plug-patch system. My BMW dealership has both.

A good lever-less tire machine is so automated that a 10 year old could use it without screwing up your rims.

https://www.youtube.com/watch?v=N_FzyGqunUE
 

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Hi all. When. I first got my 528 I had the dealer put nitrogen in the tires. For the last year it's been great.
Race teams use nitrogen to aggressively manage tire pressures. Nitrogen still leaks out. Consumers Reports did a test and found that pure nitrogen leaks out at about 80% the rate of air.

I have plain old air in my tires and they leak down about one PSI every two weeks.
 

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As Fall approaches in the northern climates it is probably good to review the following:


Tire pressure can change with fluctuations in temperature. So, how should you correctly monitor tire pressure as the outside temperature changes?

First, it's important to remember that gas expands when heated and contracts when the temperature declines. In North America, the daily temperatures rise and fall between day and night, as well as seasonally. As the days get shorter and colder during fall and winter, it's especially important to check your tire pressure.

Second, it's important to know that the recommended tire pressure for your vehicle (as specified in the owner's manual and the tire placard for the vehicle) are both based on cold inflation pressure. This means that the tire pressure should be checked in the morning before the tire has been run, before the ambient temperature rises during the day, and before the tire is exposed to direct sunlight.

A good estimate to use when comparing tire pressure to air temperature is for every 10 degrees F, tire pressure will adjust by 1 psi. For example, if the outside air temperature increases 10 degrees, the tire pressure will increase by 1 psi. Conversely, if the air temperature falls 10 degrees, the tire pressure will decrease by 1 psi.

In most parts of North America, the difference between average summer temperatures and average winter temperatures is about 50 degrees F. This means that your tires will fluctuate approximately 5 psi (assuming no other air loss) between the coldest and warmest times of the year. A drop of 5 psi during colder months will affect traction, handling, and durability. This is why it's important to remember to check your inflation pressure, especially during colder times of the year.

In most parts of North America, the average daily air temperature fluctuates by approximately 20 degrees F. Using our rule-of-thumb formula from above, this means that the inflation pressure can fluctuate by approximately 2 psi during the day. This fluctuation can be even more pronounced if the tire is subject to direct sunlight.

In addition to changes from sunlight, the tires temperature is also affected by driving. Tire pressures can increase by up to 5 psi in the first 20-30 minutes of driving, before finally stabilizing.

If you live in a cold climate and have a heated garage, the opposite problem can occur. As soon as you leave the confines of your heated garage and go out into the colder weather, your tires can lose inflation pressure. Again, for every 10 degrees F dropped, the tires will lose approximately 1 psi each.

In all three scenarios, the same problem arises, regardless if you check the air pressure when the tires are warm from driving, when there are ambient temperatures, or if the tires are in direct sunlight. If the inflation pressure is correct when a tire is warm, then it will likely be anywhere from 2-5 psi under-inflated when it is cold.

Bottom line -- you should always check your tire inflation pressure when your tires are cold, and inflate them to the recommended pressure at that time.
 

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You want to find a place with a lever-less tire machine. This will prevent the rim from getting scratched up during the removal of the tire from the rim. These machines are relatively new and relatively expensive. So, don't expect Midas, etc. to have them. Your best bet is a high-end new car dealership (BMW, M-B, Porsche, etc.). You also want to have them use a high-speed plug-patch system. My BMW dealership has both.

A good lever-less tire machine is so automated that a 10 year old could use it without screwing up your rims.

https://www.youtube.com/watch?v=N_FzyGqunUE
That video was good! They did a great job with the 10 year old and teaching him how to maneuver the Hunter machine.
 
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