Tyre care in Bahrain's summer heat

What heat actually does to a tyre

A tyre is a flexible structure that makes heat as it rolls. The air inside warms, expands and raises the pressure, which is normal and designed for. Trouble starts when road and air heat is added to the heat the tyre is already making for itself, usually because it is underinflated, overloaded or old.

Sun-exposed asphalt can be far hotter than the air, and a parked tyre absorbs that heat with no airflow to cool it. Over time, heat and ultraviolet light break down rubber compounds, so a tyre in the Gulf can age faster than its mileage suggests.

• Pressure rises as a tyre warms, so a reading taken after driving is higher than the cold figure.
• Heat speeds up oxidation and ageing inside the tyre, not just on the surface.
• An underinflated tyre flexes more, and that flexing makes still more heat.

Check pressures cold, using the placard

Cold means the tyre has not been driven on for a few hours, or has covered only a short distance at low speed. First thing in the morning is ideal. If you can only check after driving, expect a high reading, and adjust to the cold specification later rather than letting air out to reach it.

The figure you want is on the vehicle placard: commonly a sticker in the driver's door jamb, sometimes on the fuel filler flap or in the handbook. It is set by the vehicle maker for that car. The large number moulded into the sidewall is the tyre's maximum permitted cold pressure, not a recommendation.

Never bleed air out of a hot tyre to bring it back to the placard figure. You will leave it underinflated once it cools, which is the condition that causes heat damage. Let it cool and measure again. If a tyre reads low when cold, inflate it to the placard figure and then look for the reason, particularly if the same tyre is low again a month later.

Underinflation in the heat is the combination to avoid

Sudden tyre failures in hot weather commonly trace back to a tyre that ran soft for a long time rather than to one dramatic event. The sidewalls flex further on every rotation, heat builds inside the casing, and the bond between rubber and steel belts can degrade. The damage accumulates quietly, then shows up as a vibration, a bulge or a failure at speed.

Check all four tyres and the spare at least monthly, and before any long drive. A pressure monitoring system is useful but is commonly designed to warn you once pressure is already well down, so it is a safety net rather than a replacement for a gauge. A tyre that keeps needing air has a fault worth finding.

Load works the same way. A car carrying a full set of passengers and luggage needs the pressure the handbook specifies for that load, and the load index moulded on the sidewall has to suit the vehicle in the first place. Heat, load, speed and pressure all act together, which is why one soft tyre on a hot motorway is a far bigger problem than the same tyre around town.

Ageing, cracking and the car that sits in the sun

Rubber ages whether the car moves or not. Ultraviolet light, ozone and repeated heat cycles leave fine cracks, often first visible in the sidewall or at the base of the tread grooves. Surface crazing alone is not always serious, but it is a reason to have the tyre inspected, because the internal structure cannot be judged from outside.

If the car lives outdoors, shade or a cover reduces the exposure, and moving a rarely used car occasionally helps too. The last four digits of the DOT code on the sidewall give the week and year of manufacture, which is the tyre's real age.

• Look along the sidewalls and inside the grooves, not only at the tread face.
• Check the spare; it ages in the boot and is often found flat at the worst moment.
• Age limits vary, so follow the tyre maker's guidance and your vehicle handbook.

Getting ready for a long highway run

A causeway trip or a long motorway run is the hardest work most tyres in Bahrain do: sustained speed, full load, hot surface, little chance to cool. Many handbooks list a higher pressure for a fully loaded vehicle or for sustained high speed, so use that figure rather than the everyday one when the car is packed.

Before leaving, set pressures cold, then walk round the car looking for cuts, bulges, embedded nails or screws and uneven wear. Confirm the spare is present and inflated and that the jack and wrench are there. A working pressure gauge of your own is worth carrying.

• Use the loaded or high-speed pressure from the handbook when the car is full.
• Inspect tread and sidewalls before you set off, not at the destination.
• Confirm the spare, the jack and the wheel tools are present and usable.

If something feels wrong at speed

A new vibration, a rhythmic thumping, a pull to one side or a changed steering feel deserves immediate attention. Ease off the accelerator gradually, avoid heavy braking or sudden steering, and stop somewhere safe away from traffic before inspecting. Never keep driving on a tyre that is flat, bulged or showing cords, and do not test it by driving faster.

If you are not sure what you are looking at, the team at Wagon Wheel in Salmabad can check pressures and tread, read the date code and talk you through what they find.