Run-flat tyres (RFT) are designed to support the vehicle's weight and continue driving for a limited distance after a complete loss of inflation pressure, through reinforced sidewall construction that prevents the tyre from collapsing under load when deflated. The two main designs are: self-supporting run-flats, which use a rigid reinforced sidewall rubber that carries the vehicle weight when the air pressure is lost; and support ring run-flats, which use a rigid foam or hard rubber insert inside the tyre that the wheel bears on when deflated. When a run-flat tyre loses pressure, the driver can typically continue driving at a maximum of 80 km/h for up to 80 km to reach a tyre repair facility — eliminating the need for a spare tyre and roadside tyre change. Run-flat capability comes at the cost of a stiffer, less compliant ride quality compared to conventional tyres of equivalent specification, because the reinforced sidewall cannot flex as much under normal driving conditions.
Run-flat tyres provide continued mobility after a puncture without requiring a spare tyre or roadside tyre change — the primary safety benefit being that the driver does not need to change a tyre on a motorway hard shoulder. The vehicle must be equipped with a TPMS system for run-flat tyres to function safely — run-flat tyres feel similar to normal inflation when deflated due to their rigid sidewall, so the driver cannot detect pressure loss by feel alone. Without TPMS, the driver would not know the tyre has lost pressure and could exceed the run-flat's 80 km/h and 80 km operating limits, destroying the tyre and potentially causing a wheel rim failure. Vehicles supplied with run-flat tyres from the factory typically do not carry a spare tyre or full-size jack, making conventional tyre use impractical without adding spare tyre storage.
Run-flat tyre destroyed after driving without TPMS warning or beyond the limit: Driving on a deflated run-flat tyre at normal speeds or for distances exceeding 80 km generates heat that destroys the reinforced sidewall. An externally intact-looking run-flat tyre that has been driven beyond its limits has catastrophic internal structural damage and must be replaced immediately — it cannot be repaired or reused.
Run-flat tyre appearing to deflate but TPMS not warning: TPMS sensor battery has failed, or the sensor has been damaged. Run-flat tyres specifically require functioning TPMS — a vehicle with run-flat tyres and a failed TPMS sensor is dangerously compromised because the entire safety model depends on electronic pressure monitoring.
Harsh ride quality compared to previous conventional tyre vehicle: Expected with run-flat fitment — the reinforced sidewall reduces sidewall compliance by 20–40% compared to conventional designs of the same aspect ratio.
Level 1 — Owner check: Verify all four TPMS sensors are functioning at every service if the vehicle is fitted with run-flat tyres — TPMS function is the run-flat safety system. Check the tyre sidewall markings: run-flat tyres are marked with RFT, ROF (Run On Flat), SSR (Self-Supporting Runflat), or ZP (Zero Pressure) depending on the manufacturer.
Level 2 — Detection: If a run-flat tyre has experienced a complete pressure loss, it must be replaced regardless of external condition. Do not allow a workshop to declare a run-flat as serviceable after deflation without verifying it was driven within the 80 km/h and 80 km limits and inspecting the internal sidewall structure.
Level 3 — Professional service: Run-flat tyres cannot be repaired by conventional plug-and-patch methods in most cases — the reinforced sidewall construction prevents the internal inspection required to confirm structural integrity after any penetration. Replacement is the standard repair for a punctured run-flat tyre.
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