Home' Trinidad and Tobago Guardian : February 27th 2015 Contents BMW has always been in the forefront
when it comes to both auto safety and per-
formance. These days almost every BMW
comes with "run flat" tyres. Not that these
tyres actually run flat; they simply do not go
flat even though they are empty of air.
Airless, the tyre supports itself- and the
car- on stiffened panels in the sidewalls. With
no noticeable alternation in performance, the
airless tyre can be run at speeds up to 55 mph
for 50 to 150 miles depending on the vehicle.
Run flat tyres offer convenience- there is no
need to carry and store a spare tyre, so you
save space in your trunk. If safety is an impor-
tant issue for you- and it should be- run flat
tyres gives an extended mobility since they
can be driven to certain distances without loss
of control, which might lead to an accident.
Because women drivers are still at greater risk
than male drivers when stranded at roadsides,
run flat tyres allow you to drive to safety and
replace or patch the hire then- what a com-
As public awareness increases, on a local
front auto suppliers are offering run flat tyres
in varying sizes and different brands. One
such business is Race Trac Wheels based in
Arouca. Owner, Andy, says that they are avail-
able in special orders and they also have Nitto
In the event that you choose to switch to
run flat tyres, this issue of CarTalk has cov-
ered some important elements to consider,
How does run flat tyres work?
Run flat tyres have a reinforced sidewall
that keeps the tyre beads firmly seated to the
wheel rim making them capable of supporting
the weight of the vehicle without any air pres-
sure in the tyre.
How fast and how long can I use them for?
Run flat tyres are designed to get the vehi-
maximum speed of 55mph and for up to 50
How do I know if I have run flat tyres fitted?
If you look at the side wall markings they
will tell you, see below for manufactures
markings, you will also have a tyre pressure
monitoring systems (TPMS) fitted to let you
know if you have a low tyre pressure. Note
TPMS can also be fitted to normal tyres.
Can Run-flat tyres be fitted to any car?
No, Runflat tyres should only be fitted to
vehicles that come with Runflat tyres as origi-
nal equipment and have a TPMS. Any vehicle
that has Runflat tyres requires a TPMS or the
driver might not realise that a tyre has been
punctured. Furthermore, Runflat tyres are
specifically tuned to the suspension of individ-
ual vehicles meaning they are inappropriate
for fitment to other vehicles.
If one of my Runflat tyres sustains a punc-
ture can I replace it with a standard tyre?
Bridgestone do not recommend mixing
Runflat tyres and standard tyres on the same
vehicle, even if paired in axle sets. If you have
a puncture, the Runflat tyres are designed to
permit you to proceed to a tyre dealer where
you can have the tyre checked and replaced if
necessary with another Runflat tyre. In ex-
ceptional and emergency circumstances a
conventional tyre of the same size can be fit-
ted. It must be noted that standard tyres do
not have Runflat characteristics and should be
removed at the earliest opportunity.
Run flat tyre markings
Below are the side wall markings of all the
main tyre manufactures
They maybe marked RSC (R-un flat S-ystem
C-omponent), or with one of the below
• Bridgestone= RTF (Run Flat Tyre)
• Dunlop= DSST (Dunlop Self-Supporting
• Firestone= RTF (Run Flat Tyre)
Goodyear= EMT (Extended Mobility
• Kumho= XRP
• Michelin= ZP (Zero Pressure)
• Pirelli RFT= (Run Flat Technology)
• Yokohama= Run Flat
• RTF Run Flat Tyre
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An article in the Italian newspaper La Repubblica (www.larepubblica.it) spilled the
beans with step-by-step instructions, which are pretty valid regardless whether you are
Christina Aguilera or Queen Elizabeth:
"A woman with a short skirt gets out of a car with underwear on. She keeps her legs together
and swings the legs sideways by turning herself towards the door before it is opened. A lady
never opens her legs in public."
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