With the unsettling rise in road spiking incidents, where sharp objects are deliberately placed on roadways to damage vehicles, drivers are more vulnerable than ever. Road safety has become an increasing concern, particularly when it comes to how tyres respond to such hazards. To help drivers better understand the risks and how to navigate these dangerous situations, Keith Phelps, leading technical tyre expert at Dunlop Tyres SA, shares invaluable insights in a Q&A format. Here’s a breakdown of how tyres react to impacts, practical advice, and vital safety measures every driver should know.
How Will a Driver Know They’ve Driven Over Something That Has Impacted Their Tyres?
When a tyre is punctured by a sharp object like a spike, it’s often immediately noticeable. The first sign is a distinct hissing noise, followed by the vehicle pulling to one side or a noticeable vibration in the steering wheel. These are clear indicators that something has compromised the tyre’s integrity.
What Happens When a Tyre Hits a Spike?
Tyres are designed to maintain air pressure and support the weight of the vehicle. When a tyre hits a spike or sharp object, particularly if it’s severely under-inflated, it can cause catastrophic damage. The steel protector breaker plies inside the tyre can break, leading to sudden deflation, which is referred to as run-flat tyre damage. This kind of damage compromises the tyre’s casing or carcass integrity, making it unrepairable. It’s critical to note that if such damage occurs and the tyre is repaired, it will fail when put back into service.
Does Speed Play a Role in the Type of Damage Sustained?
Absolutely. Speed is a crucial factor in the severity of tyre damage. A high-speed impact with a large object, like a road spike, can result in a tyre bursting, causing the driver to lose control of the vehicle. However, if the driver is travelling at a slower speed, the sidewall of the tyre has more flex, which can help mitigate the impact, potentially allowing the driver to maintain better control, and reducing the likelihood of the tyre bursting.
What Happens to the Tyre and Its Structure Upon Impact?
A sudden deflation caused by an impact with a spike will lead to severe damage, often referred to as run-flat damage. This impacts the tyre’s inner liner and damages the casing or carcass plies. With insufficient air inside the tyre, the vehicle’s handling is severely compromised. The car will tend to pull to one side, and the driver may feel vibrations through the steering wheel. This will also affect braking, increasing the risk of losing control of the vehicle. If you experience a sudden deflation, the key is not to brake abruptly. Instead, maintain a firm grip on the steering wheel to keep the vehicle moving in a straight line. Sudden braking shifts the weight of the vehicle in a way that could cause further loss of control.
What if I Don’t Want to Step Out of My Car to Check My Tyre Damage?
In the unfortunate scenario of road spiking, safety should always come first. If you feel vulnerable and prefer not to stop and check the damage, continue driving on the flat tyre until it’s safe to do so. Keep your speed low, around 30-40 km/h, and head towards a secure location. Inform local authorities about any suspicious activity, and share your live location with a trusted family member or friend. Remember that tyres and rims cannot be repaired after such damage and must be replaced.
Can I Drive on a Punctured Tyre?
If you’re in a potentially dangerous situation, it’s better to drive cautiously and make your way to safety. Driving on a punctured tyre at a reduced speed (30-40 km/h) can prevent additional damage and help you get to a safer place. However, continuing to drive on the damaged tyre will cause severe run-flat damage, affecting the casing and possibly resulting in a breakup of the tyre’s structure, depending on the vehicle’s weight and speed. Additionally, the rim could spark if it’s a steel rim, while alloy rims may cause more significant damage due to their softer material.
Is There a Difference Between Having One Tyre Damaged, or Many, and Is One Tyre More Important Than the Others?
While all four tyres are critical for the vehicle’s stability, the tyres on the steering axle (front tyres) are particularly important. If these tyres are damaged, it can compromise the vehicle’s handling and braking performance. In fact, approximately 70% of a vehicle’s braking ability comes from the steer axle. On the other hand, if the rear axle tyres are impacted, the vehicle will remain more controllable because only 30% of the braking is dependent on the rear tyres.
Are Newer Technology Tyres Designed to Withstand Such Impacts?
While modern tyres are built to withstand a range of impacts, they are not designed to endure deliberate road spiking. Some high-end vehicles, especially military vehicles, are equipped with run-flat inserts in their tyres, but this is not standard due to the high cost involved. Motorists can consider using aftermarket tyre sealants, which can help buffer small punctures caused by screws or nails. However, these sealants may not be effective against larger objects like spikes.
What Tyre Products or Tools Can I Carry to Repair My Tyre?
It’s advisable to carry a temporary tyre repair kit, though remember that this is only a short-term fix. A small compressor powered by the vehicle’s battery is another useful tool, as it can inflate the tyre enough to help you get to a safe location. Always remember that these solutions are temporary, and damaged tyres must be replaced as soon as possible.
How Do the Right Tyres and Regular Tyre Maintenance Help Minimise Impact?
Just like maintaining a strong immune system helps you fight off illness, regular tyre maintenance ensures your tyres are in the best possible condition to withstand impacts. Using the correct tyres for your vehicle and intended use is essential. For example, severe off-road conditions require more durable 3-ply sidewall tyres. Consult a tyre expert at your local tyre dealer to ensure you’re using the right tyres for your needs. Regular maintenance, including checking for bulges, cracks, and proper inflation, will help keep your tyres in top shape, reducing the likelihood of serious damage in emergency situations.
Tyre Maintenance Advice:
- Inspect tyres for potential damage or vulnerabilities once a week.
- Perform regular cold inflation checks, ideally weekly, to ensure proper tyre pressure.
- Regularly check wheel alignment and balancing.
- Rotate tyres every 8,000 to 10,000 km to ensure even wear and optimal performance.
Conclusion
Safety is paramount when it comes to tyre performance, especially in the face of increasingly concerning road spiking incidents. By understanding how tyres respond to impacts and taking proactive measures such as maintaining proper tyre pressure and using the right tyres for the job, drivers can improve their chances of navigating such hazards. Always remember: quick thinking and careful decision-making are key to protecting both yourself and your vehicle in emergency situations.
