Car tyres have been rolling us along for a long time — thanks to inventors such as John Boyd Dunlop and Charles Goodyear who worked more than 120 years ago to develop and refine what we have today.
But one thing which hasn’t changed since those early days of pneumatic tyres is the need to inflate them correctly.
This is not too much to ask really; the New Zealand Automobile Association points out that finding the right tyre pressure for your car is easy. You can find this information in the handbook or it can often be found on a sticker inside the fuel filler flap or the driver's door.
These points of information will generally show two figures – one for 'normal' use and a higher figure for full loading.
If you regular carry heavier loads in your vehicle then bear in mind that you may need to increase the pressure in your tyres. If you can't find the tyre pressure details yourself, the AA says it's best to contact the vehicle manufacturer or try searching for your pressures using your registration number on the EECA Energywise New Zealand website.
Regularly checking your tyres is important:
- If a tyre is flat, it will wear prematurely. Over-inflated tyres will cause one part of the tyre to contact the road more, potentially causing this part of the tyre to wear faster.
- A flat tyre doesn’t roll as efficiently, therefore increasing fuel consumption.
- Optimum pressure in your tyres will give the best grip and safe braking threshold.
- Under-inflation can cause steering wheel wobble, increased steering effort and unstable cornering.
AA recommends drivers check tyre pressure every couple of weeks. If possible, make the checks when the tyres are cold and always use a reliable and accurate tyre pressure gauge – and don’t forget to check the spare, if you have one.
While checking the pressures, look at the tyre for any signs of wear on the tread and depth, as well as any cuts or bulges on the sidewalls. Any cuts should always be checked out by a specialist; if you spot bulges, there could be damage within the internal structure of the tyre which must be replaced.
The minimum warrantable depth for tyres is 1.5mm; to make sure tyres remain legal between warrants, take a 20 cent piece, insert it into the tread of the tyre at multiple points with the 20 facing towards you. The base of the number 20 is about 2mm from the edge of the coin, so if you can still see the whole number, it’s likely the tyres need replacing.
No spare tyre?
It’s now common for vehicles to have no spare wheel provided. Sometimes this is because the vehicle is fitted with runflats – tyres that are designed to stay intact in the event of a puncture which do not require roadside repairs.
In turn, they offer minimal driving disruption if you happen to get a puncture – and allow you to safely get to a workshop for repair or replacement.
For vehicles without runflat tyres fitted, sometimes a method of inflating and temporarily sealing the punctured tyre in order to get you to the nearest practical place for repair is offered instead.
Tyre sealant is a still relatively unknown product but, similar to runflats, it’s designed to offer a temporary repair to allow you to get to a place where the tyre can be taken in for a replacement