Once upon a time

Published in the November 2016 issue of “Die Porsche Kassette”

Ⓒ2016 Technolab / PedrosGarage.com

Graphics courtesy of Bridgestone Tire Co.

Once upon a time ....        by Pedro P. Bonilla (GCR PCA)

Once upon a time


For more information on Run Flat Tires and more, please visit my website:

www PedrosGarage.com.



Happy Porsche’ing,

... Porsches came with a nice set of tools which included a jack, and a lug wrench, and a standard or collapsible spare tire!

But those times are long gone.

In order to save weight and

manufacturing costs, they did

away with all of that in 2005.


But this deletion is not an

exclusive Porsche move. 

Most car makers adopted

the same policy.


You do get a can of Fix-a-Flat

and an air compressor, but I

wouldn’t recommend using that slime at all.

It makes a mess and will cost a pretty penny to clean from the wheel.

My recommendation is to carry a tire plug kit and a 12 volt air compressor (both available at most auto part stores).  Also make sure your AAA payments are up to date and don’t forget your cell phone in order to call the flat bed if you can’t or don’t want to fix the inevitable flat tire.


You may be thinking:
“But wait, I don’t need a flat bed or a tire plugging kit because if Porsche didn’t include a spare tire or tools that means that my car came with run-flats, right?”

Well, you would be wrong if you assumed that.


You can install aftermarket run-flats although they are very limited in sizes and widths and are also more expensive.

I you purchased your car used and you wonder whether it has run-flats, you can check the tires themselves.  They would have one of the RFT (Run Flat Tire) symbols on the sidewall.

So, should you install run-flats as your next set of tires?

First, a little more info on RFTs.

There are two basic classifications: Self Supporting Tire and Support Ring System.

If you can find them your car’s size and you’re OK with the extra cost you may still want to consider the following:

RFTs should only be installed on cars equipped with TPMS (tire pressure monitoring system) because if you get a puncture and loose air pressure on a RFT you may not know it due to the extra stiffness of the sidewalls.  RFTs don’t flatten down when they lose air pressure, they look and drive pretty normal, but RFTs can only be run 50 - 100 miles at a max speed of 55 mph once they lose air.  Then they MUST be replaced.  They cannot be repaired and/or re-inflated.


In my opinion, the only real advantage of RFTs is that when you get a puncture, you don’t have to pull over immediately to change or fix the flat, which is good if you’re on a heavy-traffic road or dangerous otherwise, and in racing, where having to pull into the pits for a flat could cost you the race, especially if it happens on the closing laps and you have the lead.  Many track tires are now available as RFTs.


More tire manufacturers a expanding their RFTs so you may be able to find a set that fits your car.  Some sport cars, such as Chevrolet’s Corvette now come wit RFTs standard.  Maybe Porsche will follow suit.

Self Supporting Tires have reinforced sidewall construction that continues to support the vehicle even with total loss of pressure.  This allows for continued operation up to the speed and distance specified by the manufacturer.

Support Ring Tires employ a ring of hard rubber or other structure that can support the vehicle’s weight in a complete air loss condition.

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