Services and Information

"Under-inflated tyres will wear more quickly and there is a greater risk of a puncture"

Tyres and Wheels

Modern tyres are not just giant lumps of rubber moulded into shape. Although some natural rubber is still used in their construction, they are now a complex blend of a huge range of materials including steel, rayon, nylon, polyester and carbon black. The exact composition of this compound will determine the tyre's characteristics.

Every tyre has a sidewall marking which identifies its size and characteristics. These markings can be analysed as follows:


185/70 R14 80 T

185 The width of the tyre in millimetres.
70 The aspect ratio - this is the ratio of the tyre's width to its height or 'sidewall'. A '70 series' tyre is a tyre whose height is equal to 70% of its width. Low profile tyres have shallow sidewalls and correspondingly low aspect ratings.
R This denotes the tyre's construction type - in this case it's a radial.
14 The diameter of the wheel rim in inches
80 Load index - this represents the maximum load capacity of a tyre when it's driven at maximum speed. A tyre with an Li of 80 can bear a maximum load of 450kg.
R Speed rating - all tyres carry a speed rating which indicates the maximum speed for which the tyre was designed. An R rated tyre should not be driven above 170km/h (106mph). A V rated tyre, by contrast, is capable of speeds of up to 149mph.

Tyre age

The sidewall also carries a three digit age code indicating when it was made. For example, 124 means the tyre was manufactured in December 2004

Air pressure

It's important to check your tyre pressures every month and to compare them with the correct ratings as described in the vehicle handbook. Under-inflated tyres will wear more quickly and there is a greater risk of a puncture. Over-inflated tyres also puncture more easily and can create erratic handling characteristics

Damaged tyres

Never drive with damaged tyres, which carry an increased risk of a puncture.