Spare Tyre

The spare tyre serves as the "last line of defence" in vehicle chassis safety. Although modern vehicles boast ever-improving reliability and many models now come equipped with run-flat tyres or tyre repair kits, the spare tyre remains indispensable when dealing with irreparable sidewall damage.

Types of Spare Tyres

Full-size spare tyre: Identical in size and specification to the vehicle's four factory-fitted tyres. Its main advantage is that the vehicle can continue driving normally after fitment without speed or mileage restrictions, and it allows for a 5-tyre rotation to extend the overall lifespan of the tyres.

Space saver / Temporary spare tyre (compact spare): Smaller in volume with a narrower tread, and typically fitted on a smaller rim.

Limitations: Strictly for emergency use only. It usually carries a prominent speed limit marking (e.g. Max 80 km/h), and high-speed or long-distance driving is strictly prohibited.

Reason: Due to differences in rolling circumference and uneven grip levels, prolonged usage can cause severe damage to the differential and interfere with the vehicle's stability control systems (ESP/ABS).

The "Sunk Cost" and Maintenance Misconceptions of Spare Tyres

Many drivers assume that keeping a spare tyre tucked away in the boot means they are good to go, but that is far from the case: 

Pressure loss: Tyre rubber naturally loses air through micro-pores over time. If left unchecked, a spare tyre is often flat by the time you actually need it. Recommendation: Check your spare tyre's pressure every six months. It is even advisable to inflate it slightly above the standard rating (e.g. 2.8 – 3.0 bar) so that it remains within a usable range after natural air loss. 

Rubber ageing: Even if unused, tyre rubber degrades over time. If a vehicle is 6 to 8 years old, the spare tyre's rubber compound has likely deteriorated significantly, rendering it unsafe for high-speed driving.

Key Principles When Using a Spare Tyre

For transition only: The sole purpose of a spare tyre is to get you safely to the nearest tyre shop. 

Mounting recommendation: For front-wheel drive (FWD) vehicles, it is advisable to install a space saver on the rear axle. In the event of a front tyre puncture, move an original rear wheel to the front axle first, then fit the space saver at the rear. This maintains balanced traction across the front axle (which handles steering and primary braking), significantly enhancing driving safety.

Check wheel bolt specifications: Certain performance models use specialised extended wheel bolts. Due to differences in rim thickness, the spare wheel may not be compatible with the factory bolts; always verify that the bolts match correctly before fitting the spare tyre. 

Spare Tyre "Alternatives" and Their Pros & Cons

Run-Flat Tyres (RFT): 

Pros: No need for roadside tyre changes; allows you to continue driving at up to 80 km/h for around 80 km even with zero tyre pressure. 

Cons: Extremely stiff sidewalls result in poorer ride comfort. Once severely damaged (such as a torn sidewall), they are virtually unrepairable and costly to replace.

Tyre Sealant & Inflator Kit:

Pros: Space-saving and reduces overall vehicle weight.

Cons: Only effective for tiny tread punctures. It is completely useless against sidewall cuts or large punctures. Additionally, tyre sealant can foul tyre pressure monitoring sensors (TPMS), and many tyre shops will refuse to repair tyres that have been treated with sealant.