Tyre Legality

The UK law states that a tyre must be ‘fit for purpose’

This means tyres must;

  • Be compatible with the types of tyres fitted to the other wheels, not have any lump, bulge or tear caused by separation or partial failure of the structure.
  • Not have a cut or tear in excess of 25mm or 10% of the width of the tyre, whichever is the greater, and which is deep enough to reach the ply or cord.
  • Not have any part of the ply or cord exposed.
  • Have a minimum legal tread depth of 1.6 mm, and be showing 75% of tread pattern which must be central to the tyre

A vehicle with any of these faults, or with tyres of different nominal size or aspect ratio on the same axle, is liable to fail an MOT test.

You can take a rough measurement of tread depth with a 20p coin*

  • Place 20p in the tyre tread.
  • Look at the coin with your eyes level to the tyre’s surface.
  • If the border of the coin is in full view – the tyre is illegal

* This method is not an exact method of measurement

Tyre Labelling

How to read and understand tyre labels.

New EU legislation came into force in November 2012, whereby all tyres sold must be clearly labelled to advise the consumer on fuel efficiency, wet grip road holding, and exterior noise levels.  Every tyre sold now will have one of these labels – if not the tyre is old stock.

For fuel & wet grip, ‘A’ is the best performing and with exterior noise levels, if you want the tyre as quiet as possible, the lowest decibel (dB) number is required.

Tyre Markings

How to read and understand tyre markings.

The markings and writing on your tyre not only state the brand and model of the tyre, but also the sizes, width, aspect ratio, and load and speed rating.

But what does that mean? Putting the branding to one side, let’s focus on the numbers and letters.

For example, a tyre may say 205/65/R16 . This would mean that the tyre is 205 mm wide, the 65 is an aspect ratio. This ratio is what the height of the tyre sidewall is, in relation to its width. So in this example, the tyre wall is 65% of the tyres width.

Next is R16 , which tells us two things, the ‘R’ , that the tyre is of radial construction, the 16 tells us what diameter wheel these tyres are designed for.

So this tyre is telling us it’s a radial tyre, 205 mm wide, with a tyre wall 65% of its width, which will only fit 16 inch wheels.

The next two sets of numbers and letter are the load index, and speed rating. So if we use the same 205/65/R16 tyre, we now see a number and a letter.

The number is the load index, this tells us the weight that each tyre can carry, the letter is the speed rating, denoting what maximum speed the tyre can safely drive at.

So from the example, we see that this tyre has been rated 95 V . From the charts below we can see that this tyre is rated to carry no more than 690 KG per wheel. So a total vehicle weight of 2760 KG ( the average vehicle weight being about 1,400KG ) is permitted. The speed rating on the example tyre V, means that it is not recommended by the manufacturer to exceed 150mph.

These ratings may seem high but they need to accommodate unrestricted roads such as the Isle of Man and the German Autobahns.

Book a free tyre check at MOTEST and stay safe

Good tyres are critical to ensure you and your passengers are safe. Not only is it dangerous to drive round with faulty tyres, it can also cost you 3 penalty points and up to £1000 fine for each defective tyre!

That why MOTEST are happy to help with this free four point check on all tyres

Check all tyres including spare for general condition
Check all tyre pressures are correct
Check tread depth and pattern for legality
Check if front tyres show excessive or uneven wear pattern