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Tyres are possibly the most important single part of the car. As they provide the contact with the road in a straight line or under the stress of a corner or braking.


At Clock Garage, Blackburn we will advise you on the correct tyres and whether your current tyres need replacing.


We have included this quick guide to give you an idea of how we go about checking your tyre is legal and safe. Uynlike many tyre centres we will not advise you to change all four tyres unless neccessary. However it is a good idea to change tyres on the same axle to ensure the you have the same grip. When changing a tyre we will check the vehicle tracking and correct it if neccessary, to ensure that the car is safe for your journeys.


On your tyres you will find the numbers illustrated below.

The last number and letter are the load rating & speed rating. The load rating is the maximum load that the tyre can sustain at 130mph. The speed rating is the maximum speed the tyre can sustain for 10 minutes without falling apart. 

The first number is the width of the tyre from one side to the other in milimetres.

The second number is a percentage of the 1st number that shows the height of the tyre. E.g the height of this tyre shown would be 35% of 275 which is 96.25mm 

Next is R19. R = Radial. All tyres are now Radial so this letter isn't imporant as it used to be. The number is the wheel diameter that the tyre will fit on in inches. 


For peace of mind we recomend you check your tyres at least once every two weeks. You need to check:


  • Tyre tread depth: The legal limit for this is 1.6mm across 75% of the tyre width, most manufacturers have a tread depth indicator set at 2mm. We recommend you change the tyres before reaching this though.


  • Tyre pressure: If your tyres are not inflated correctly they will wear out more quickly and most improtantly will not work correctly when needed. Check your manual for the correct pressures for your car and then use a gauge to check as visually the tyres may look fine.


  • Tyre wear: If the tyres are wearing across the entire width this indicates incorrect inflation. If they are wearing at one side then the tracking of your car needs checking. You also need to check the tyre wall for wear, both the outside and the inside.


  • Final tyre check: Don't forget your car has FIVE wheels, the spare needs regular checking for correct inflation and any damage. If you do need to use your spare tyre only use it to get to a garage to get the tyre changed. Especially if it is a space saver spare. These are only designed for low speed and essential driving


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