Runflat Tyres
Feeling Flat
Runflat tyres allow you to drive on deflated tyres for a short time and distance, but how do they work?
Runflat Tyres, The sidewalls of run-flat tyres can be up to 50 percent thicker than traditional tyres. The sidewalls are capable of carrying the weight of the vehicle when the tyre is flat, and this is achieved by layering rubber and heat-resistant cords. The tyres also have a beaded rim that grips the wheel when flat to avoid air leakage or blow out. Self-supporting tyres are so good at masking the traditional loss-of-air symptoms that accompany a flat tyre, they require a tyre pressure monitoring system to alert the driver that they have lost air pressure. Without such a system, the driver may not notice underinflation and may inadvertently cause additional tyre damage by failing to inflate or repair the tyre at the first opportunity.
Runflat tyres are fitted to special designed wheels with a auxiliary support system for increased effectiveness. A ring is designed into the wheel allows flat tyre tread to rest on the ring, taking the pressure off of the tire, which eventually wears out and puts it on to the wheel which rarely requires replacement.
Tyre Shop recommend only fitting runflat tyres onto runflat wheels as they have been designed to work together to get you home safely. We also advise not to change from runflat tyres to normal tyres for the same reason.
A run flat tyre is a tyre that is designed to resist the effects of deflation and to enable the vehicle to continue to be driven - at reduced speeds (i.e. 80 km/h) and for limited distances (80 km).
There are also issues with repairing punctures in run-flat tyres if the puncture is in the side wall or near the edge of the tread.
Self-supporting tyres feature a stiffer internal construction, which is capable of temporarily carrying the weight of the vehicle, even after the tyre has lost all air pressure. To provide "self-supporting" capability, these tyres typically attach rubber inserts next to or between layers of heat-resistant cord in their sidewalls to help prevent breaking the reinforcing cords in the event of loss of air pressure.These tyres first provide a seal around the object when the tyre is punctured and then fill in the hole in the tread when the object is removed. Because these tyres are designed to seal the tyre immediately upon being punctured, most drivers will never even know that they just had a puncture.
Self-sealing tyres are designed to fix most tread-area punctures instantly and permanently. These tyres feature standard tyre construction with the exception of an extra lining inside the tyre under the tread area that's coated with a puncture sealant that can permanently seal most punctures from nails, bolts or screws up to 3/16 of an inch in diameter.
Also because these tyres feature standard tyre constructions, the traditional loss-of-air symptoms that accompany a flat tyre remain to warn the driver if the tyre is damaged beyond repair.
Typically, Runflat & Self-supporting tyres maintain vehicle mobility for 50 miles at speeds up to 55 mph. Examples: Bridgestone RFT (Run Flat tyre), Dunlop DSST (Dunlop Self-Supporting Technology), Firestone RFT (Run Flat tyre), Goodyear EMT (Extended Mobility Technology), Kumho XRP, Michelin ZP (Zero Pressure), Pirelli RFT (Run Flat Technology) and Yokohama Run Flat. Auxiliary Supported Run Flat Systems Auxiliary supported systems combine unique wheels and tyres used for Original Equipment vehicle applications.
The advantage to this type of system is that it will place most of the mechanical task of providing run flat capability on the wheel (which typically doesn't wear out or need to be replaced), and minimizes the responsibility of the tyre (which does periodically wear out and requires replacement). Additionally, auxiliary support systems promise better ride quality because their sidewall's stiffness can be equivalent to today's standard tyres.
The Tyre Shop stocks and fits all manufactures of Run-flat tyres at home or at work its far more convenient.