Merityre Article Archive

What hurts more, being fined for using illegal car tyres or paying out so your car tyres are legal and safe? In practice, the latter cancels out the former. However, it pays to know what the law requires of you in relation to your car’s tyres. Here is a breakdown of the legal necessities as regards car tyres.

Driving on worn or damaged tyres can attract a fine (or an MOT failure) and it can also place you firmly in breach of your car insurance policy’s conditions. Both these events matter but something else you may be doing is of far greater importance. Never forget that using tyres that are of the wrong type, are damaged or are worn endangers lives.

Important points

What makes a car tyre poor? Several aspects can put a tyre in this category but there are important factors you need to consider…

Car tyres must not have any lumps, bumps or tears caused by separation or partial structural failure.

They must not have a cut or tear longer than 25 millimetres, or longer than 10 per cent of the width of the tyre’s section (whichever is the greater). No such damage may be sufficiently deep as to reach the tyre’s internal cords.

No part of the tyre’s internal plies or cords may be exposed.

Any tyre must be compatible with the type of tyres fitted to the other wheels

Any tyre, on a car or trailer, must be fit for purpose and free from any defect that might endanger any person or damage the road.

Legal tyre maintenance

All car tyres have to be correctly inflated, to the car maker’s and tyre manufacturer’s recommendations. It is acknowledged that under certain circumstances, ‘run-flat’ tyres may be used in an uninflated or partially inflated state. 

How much tread?

The legal minimum tread depth requirement for a car tyre is, ‘at least 1.6mm throughout a continuous band in the centre 3/4 of the tread and around the entire circumference.’ This tread depth must not fall below the legal minimum and the original tread pattern must be visible.

Must I carry a spare?

In law, you aren’t obliged to carry a spare tyre and nor need one meet legal requirements when it is stored in or under the car. However, if a spare tyre is used, it must comply with all the above legal requirements.

The Penalties

Now for the bottom line. What will illegal tyres cost you? Read on, carefully…

If you use a vehicle with one or more defective or illegal tyres, a police officer can issue a Fixed Penalty Notice (a Conditional Offer Notice in Scotland).

At his or her discretion, a police officer may decide not to issue a Fixed Penalty Notice but may report the case for prosecution.

Both the car’s driver and its owner (if he or she is not the same person) are liable. One or both may be issued a summons. 

A court can impose fines up to a maximum of £2,500, and three penalty points. This relates to a car; the financial penalty for a goods vehicle or for one built or modified to carry more than eight passengers can be double this amount.

If a car has more than one defective tyre, a summons can be issued for each illegal tyre.

Under certain circumstances, disqualification becomes possible.

Sobering reading? Certainly, but this is probably less punitive than the physical costs of a car accident caused by an illegal tyre.

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A car exhaust system usually has one important characteristic. The fact that it is capable of keeping poisonous gases safely away from the car’s passengers? No. The fact that it can reduce a loud, raucous noise to a tasteful refined humming? No. The fact that it’s catalytic converter can trap harmful particles and noxious gases, therefore keeping the environment cleaner? No, it’s none of these. The important point is that most people only pay attention to their car’s exhaust system when it goes wrong.

Sadly, the notion of the everlasting car exhaust is a mere pipedream. Looking at what a car exhaust has to put up with on a daily basis soon tells us why. Have you ever seen the flames belching from a top fuel dragster with open exhausts? Your car would do the same if it had nothing but open pipes. So from a cold start, a car exhaust system has to cope with temperatures up to about 1400 degrees Fahrenheit (760 degrees Centigrade) at full load. This happens at the exhaust manifold, under the bonnet but the increasing requirement to run engines with a weak (or lean) fuel mixture leads to an increase in car exhaust temperature. For example, if the car has a turbocharger, this can be required to run at 1050 degrees Centigrade (1922 degrees Fahrenheit). Just to give you an idea what this means, 49 degrees Centigrade will burn your skin; your blood would boil at 101 degrees.

Heat isn’t all that a car exhaust has to handle repeatedly. The materials that pass through an exhaust system include nitromethane, nitric acid vapour, hydrocarbons, carbon monoxide, sulphur dioxide, particulate matter (i.e. soot and smoke), and volatile organic compounds. Many of these elements are corrosive and the presence of water as a by-product of burning petrol in the engine doesn’t make life any easier for the metal of the car exhaust.

So, your car exhaust has to cope with a lot. Is this all? In a word, no. Apart from the heating and cooling cycles and the toxic contents it must deal with, a car exhaust has to cope with mechanical stresses and strains on every journey. A car exhaust is a weighty structure that, at one end, has to deal with an engine that moves about on its flexible mountings. At the other end, the exhaust has to remain fairly still, especially when its tail pipes exit through the car’s rear panel. Then there are the demands of speed bumps, potholes and the like. The car exhaust, suspended on flexible mountings over its whole length, has to remain intact under what can be enormous transmitted forces.

The above, which is not overly detailed, constitutes a tall order by anybody’s standards. In many respects, it is remarkable that a car exhaust will last for any length of time in the face of the demands placed on it every day.  The encouraging news is that a car exhaust can usually be replaced quite quickly, at a good exhaust fitting centre.

Unsurprisingly, you can’t do a great deal to give your car exhaust an easier life. You can try to ensure any journey you make is long enough to make the car exhaust hot, which will burn out damaging internal water. You can give the exhaust system a rinse when washing the car, to get rid of corrosive salt. Above all, listen to your exhaust, it’ll soon let you know when it’s past its use by date. Finally, remember that the ‘cat’ – the catalytic converter – will need replacing at least once during your car’s lifespan.

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The Insitute of Advanced Motorists’ Drive and Survive is billed as a leading occupational driver risk management provider. The IAM is itself a leading road safety charity which has the sole aim of improving road safety for everyone. This week’s motoring tips, from IAM Drive and Survive’s head of training, Simon Elstow, involve car tyres.

Simon recommends regularly checking your car tyres, not least because the portion of each that is keeping you on the road is only the size of a footprint. Even though a car has four contact patches of this size available for use, it is important to be certain that the tyres are working optimally.

An under inflated tyre, Simon points out, will wear far more quickly than one at the correct pressure. Industry experts claim that a 20 percent reduction in pressure can rob a car tyre of up to 30 percent of its useable life. Moreover, ensuring that your tyres are inflated according to the recommendations in the car’s handbook can reduce fuel consumption by up to five percent, as compared to the cost in fuel of under inflation.

Simon Elstow also says, “Check tyre pressures when the tyres are cold, at least once a month – and weekly is far better. And don’t be tempted to over-inflate them. This causes poor vehicle handling, reduced stability during braking and cornering, and reduced grip.”

IAM Drive & Survive also recommends checking your car tyres for evidence of wear and damage. Picking up a nail while driving doesn’t necessarily mean the tyre is fit only for the scrapheap. Often, a puncture of this kind can be professionally repaired. However, damage caused to a car tyre’s sidewalls or its carcass is often a death sentence for the tyre. This is reason enough to drive carefully, avoiding potholes and kerbs. It is also a good reason for carefully inspecting your car tyres. Cuts, lumps and bulges can be a dead giveaway of further, hidden damage. It’s better to find out about such damage at pressure-checking time with the car at rest, than it is to suffer tyre failure at speed on a motorway.

The ‘tyre-kickers’ of this world are best advised to be accurate when checking tyre pressures. Why, for example, do the tyres need to be checked when cold? Because tyre pressure increases with temperature so if the tyres are warm, the pressure readings will be falsely high. So when the tyres cool down, they wind up under inflated.

Is the tyre pressure gauge at your favourite garage accurate? Generally, garage gauges are accurate but it pays to invest in your own gauge too. Why? Because under inflated tyres aren’t always easy to spot, unless the pressure in them is way too low. The two minutes it takes to check tyre pressures at home can tell you if you’ll need to put coins in the garage’s tyre machine. What’s more, with your own pressure gauge, there’s no longer the need to wonder if that at the garage is accurate. Just check it against your trusted pressure gauge.

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Merityre.co.uk are one of the  leading UK independent suppliers of car tyres. Why not visit their website for an online tyre quote or contact your nearest fitting centre.

Your car’s tyres are literally your lifeline;  they are essentially all that is keeping you on the road. Neglect them at your peril. The following 10 tips will certainly save you money and they could well save your life, and the lives of innocent bystanders.

1. Check your car tyre pressures regularly. Running tyres at too low or too high pressure causes wear and speeds the deterioration of your tyres. Moreover, too low a tyre pressure means you will use more fuel; economy can improve by 10 percent when the tyre pressures are correct.

2. Regularly check your car tyres for cuts, bulges or lumps. While the former is obvious, visible damage, the latter can indicate unseen damage within the tyre carcasses. Having a specialist check out any suspect tyres makes far more sense than risking a blowout.

3. Unless you have one of the modern onboard repair kits with a pump, always carry your spare wheel. Remember that there are limits to the speed at which space saver spare tyres can be used, and the distance they can cover.

4. Potholes are car tyre killers, they can damage not only your tyres but even your wheels. You inadvertently strike a pothole and suspect damage has occurred, check the relevant wheel and tyre as soon as you possibly can.

5. If, when checking out tyres, you find a sharp stone embedded in a tread, remove it before it does any damage. However, if you spot a nail, leave it there as pulling it out will cause the tyre to deflate. A car tyre specialist will deal with it for you and may be able to repair the tyre.

6. When checking tyre pressures, remember to replace the valves’ dust caps. These prevent dirt and debris from entering the valves and can help maintain tyre pressure.

7. If possible, keep your car in a garage. Car tyres are tough but exposure to all weathers can accelerate their deterioration. Sunlight damage is common; the ultra violet component in the sun’s rays can cause cracking and crazing.

8. When negotiating speed bumps, never straddle them. Allowing the wheels on one side of the car to pass over the bumps is no faster but it will keep your suspension and steering happier. When you encounter a speed pad running across the entire width of the road, go over it slowly.

9. When the time to replace car tyres comes, it’s best to replace all four. Should this not be affordable, you must replace two of the tyres. Having the new tyres on the back wheels is regarded as the safest.

10. Car tyre specialists don’t just sell and fit tyres. A good specialist will be happy to advise you on the best choice of tyres for your car and for the use to which you put it.

Following these simple tips means you tyres will reward you with good performance and a long service life. Conversely, ignoring your tyres can lead to unfortunate and possibly dangerous circumstances.

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Merityre.co.uk are one of the  leading UK independent suppliers of car tyres. Why not visit their website for an online tyre quote or contact your nearest fitting centre.

Changing a car wheel with a flat tyre is a relatively easy task that can be done safely, provided you follow the rules. Here’s how it can be done in five basic steps, with a few tips to maintain safe progress and make life easier.

1: Stop in a safe place, with a smooth, firm surface

Never, ever try to change a car tyre and wheel on the hard shoulder, it’s better to drive on slowly and risk ruining the tyre. Switch on the car’s hazard lights and have any passengers stand well back and away from passing traffic. Extract the spare wheel and tools from the boot, using the warning triangle if there is one. Switch on the car’s hazard warning lights.

2: Loosen the wheel nuts/bolts

Put the handbrake on, putting the car in ‘park’ if it’s automatic. Remove the relevant wheel trim or the wheel nut/bolt caps, if present. You’ll need the special ‘key’ nut to remove a locking wheel fastening. Next, loosen the wheel nuts/bolts. These usually undo anticlockwise and you should always be pushing down on the wheel wrench, not pulling upwards.

3: Jack the car up

Put a chock under the wheel diagonally opposite to the one with the flat tyre. Place the car jack under the jacking point nearest the loosened wheel – never try to use the jack anywhere else. Wind or pump up the jack until there’s enough clearance under the wheel to allow for the replacement fully inflated tyre to fit. Don’t allow any part of you get between the car and the ground.

4: Change the wheel

Turn the wheel until one of the fastenings is at the top. Remove the other three (or four) nuts/bolts first. Then unscrew the topmost fastening. Lift the wheel off, keeping your back straight and taking care not to slip. Fit the spare wheel, aligning the fastenings. Replace the topmost nut/bolt first, followed by the remaining ones. Tighten the fastenings until the wheel is fully seated on the hub.

5: Tighten the wheel nuts/bolts

Let the jack down completely and set it aside. You can now tighten the wheel fastenings firmly, working in a diagonal pattern.

You can no go on your way but there is one more step, for which you’ll need to go to a car tyre bay. Car wheel fastenings should be tightened properly and a tyre bay will use a special wrench to do this. While at the tyre bay, it makes sense to have the flat tyre repaired or replaced as necessary.

It’s also worth making some preparations before you experience a puncture; these can make life much easier.  Changing a wheel is a grimy job so carrying some industrial gloves and a mat or piece of carpet in the car can make life much more pleasant. You may also want to familiarise yourself with the wheel changing equipment. Is it accessible? Is it all there? Is the jack there? Does it need lubricating? Better to find out before the event.

Finally, have you got a space saver spare? These usually have limitations concerning speed and distance. Also, space savers can cause dashboard warning lamps to come on, because they confuse the car’s sensors. Your handbook will warn you if this is going to happen.

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It’s that time of year again. The days are short, the nights are long, precipitation is up and the mercury’s dropping. Your car’s tyres may be nearly new but there are limits to what they can do. So here are a few tips to help preserve life and limb even in the worst conditions.

There are no such things as magic tyres, despite some people’s believing that their car tyres have prestidigitatory properties. In fog, for example, your tyres won’t stop you instantly, just because you haven’t seen the line of cars up ahead in time. Equally, your tyres can’t suddenly give you enhanced grip because you need to swerve around a similar obstacle. Drive only as fast as you can see.

Rain is another condition that requires caution. Standing water in particular can be extremely dangerous.  Car tyres can dispose of surprisingly large amounts of surface water. However, when there’s too much to shift, they ride on the water surface instead. This is aquaplaning; in short, it equals no grip. Drive only as fast as your tyres will allow.

Floods are an altogether different matter. Hitting a large body of water standing a third of the way across a road at speed might give you vicious steering pull but you’ll get through if you allow for this. In deep water, your car tyres will cope admirably but your car might not. Many cars nowadays have a low-mounted air intake. If this inhales water, the engine will be wrecked. Don’t enter floodwater unless you’re certain of its depth. Keep to the crown of the road where the water will be shallowest. Keep the engine revving, to prevent water entering the exhaust and drive slowly – you have a car, not a boat. If in any doubt at all, find another route.

Snow and ice and car tyres don’t always mix. Winter tyres are a boon and it’s worth considering acquiring a set, especially if you live somewhere that experiences these conditions regularly. The usual, all-round car tyres can’t get a grip on ice and snow, even if they’re gracing a 4X4. When conditions are really bad, you may need to consider some additional hardware. ‘Snow socks’ are a new idea. These tough, woven tyre covers are easy to fit, quiet and grippy. However, they don’t last long on tarmac. The alternative is snow chains; not so easy to fit but far tougher, if noisy.

Above all, winter driving requires caution. Grip is always compromised to some extent and if you try to drive normally, losing control becomes a very real possibility. Remember also that your vision is likely to be compromised as well. Remove snow or ice from your car’s glass before moving an inch and always think about stopping distances. Modern electronic aids, such as traction control and anti-lock braking systems help but they’re no more magic than car tyres are. Should the worst come to the worst, and vision and grip both come under the general heading of appalling, you don’t have a choice. Stay at home!

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We’ve all driven past them. Tyre bays might offer the best prices, two car tyres for the price of one, special deals on four-tyre sets and all manner of other tempting offers. This is, of course, just advertising and, as Joseph E Levine said, “You can fool all the people all the time if the advertising is right and the budget is big enough.” Now, it’s true that car tyres are often a distress purchase but even so, knowing what makes is good tyre bay is knowledge worth having.

So, what makes a good tyre bay? The answer is a two-word one: products and services. Here, it is not only the range of products and services but their quality that matters. Here’s what to look for in your car tyre-buying expeditions.

It’s obvious that a tyre bay is there to sell you car tyres. What you need to know first is whether the tyre bay is going to sell you new tyres.  If you can, take a look at the stock on the shelves – you’re looking for the DOT codes. If this has three digits, walk away – four-digit codes came in after the year 2000. The way to read a four-digit code is easy to understand. The first two figures represent a particular week in the year denoted by the last two figures. So, a tyre marked 5009 was made very near the end of 2009. Car tyres have a six-year shelf life – and you can always check the tyres’ age before they’re fitted.

Speaking of tyre fitting, tyre bays have this down to a fine art. Given that car wheels and tyres live in a grimy environment, some grubbiness is acceptable even in a good tyre bay. However, untidiness should be frowned upon. If the tool cabinets are well organised, they’re liable to be well equipped. Similarly, tidy floors and a lack of overflowing bins and dead tyres underfoot denote an efficient workshop.

Wheel alignment is a service offered by many tyre bays. The days of the old Dunlop optical alignment gauge, effective though it was, are long gone. If you see computerised, four-wheel geometry wheel alignment, maybe with the involvement of measurement using lasers, you can rest assured that you’re in a good tyre bay. Remember that poor wheel alignment is a car-tyre eater.

Much the same goes for wheel balancing, which is an essential part of tyre fitting. On unbalanced tyre/wheel combinations, car tyres work less well and wear out faster. In the (very) old days, a balancing kit that involved sitting a wheel and tyre on top of a milk bottle was touted. Computerised wheel balancing is the norm nowadays – accept nothing less.

Many tyre bays are no longer transfixed, work-wise. Putting the tyre fitting and wheel balancing machinery into a van, along with an air compressor, equals mobile tyre fitting. You may take advantage of this service and some tyre bays offer a ‘call and inspect’ service, particularly for car fleet operators.

While there are other services offered by tyre bays, such as air-conditioning checks, the above suggest that a tyre bay offering these goods and services is up-to-date as well as on the ball. This in turn suggests that one very important element of tyre supply and fitment will be available and reliable. Never forget that the staff in a good tyre bay can advise you about choosing the best car tyres for your needs.

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Merityre.co.uk are one of the  leading UK independent suppliers of car tyres. Why not visit their website for an online tyre quote or contact your nearest fitting centre.

There are certain, indisputable facts in life. One is that car tyres – and car wheels – are expensive. Consequently, the, er, light-fingered among us have been known to lift our wheels and tyres, by first lifting our cars on to a convenient pile of bricks. In the relatively recent past, car alarms have become smart enough to detect when a car is being jacked up and they can tell everyone in the vicinity all about it. This is ‘active security’, which is a subject in itself. In this article, we’ll look at an example of ‘passive security’.

Passive security needs no power source: it is a barrier rather than a whistle-blower. All it need do is be there to be effective. Sometimes, passive security devices are evidently present. However, devices that mechanically prevent car wheels – and car tyres – from being stolen, tend not to shout about it.  The thieving fraternity knows what locking wheel nuts or bolts are about and it’s rare for a vehicle to lack them nowadays.

How, then, do these devices work? Their operation really couldn’t be simpler. If you attach your car wheels to your car’s hubs with four or five nuts or bolts apiece, and those nuts or bolts have a hexagon head, the danger is obvious. Replace one fastening per wheel with a fastener that needs a key of some sort to permit it to be removed and the solution is present and evident. Your wheels and your car tyres are as safe as they can be made.

The obvious question that arises is about the key itself. This, rather than being a key as such, is usually an adaptor, which allows a wheel nut/bolt spanner to be used to remove the special fastening it fits. So, what to do with the key, or adaptor? Most people keep it in the boot, or perhaps in the car’s glove box. This means your car tyres and wheels are protected by the car’s alarm. This could be worse, of course, and what is relevant is that you never know when a car tyre needs to be changed. The only watchword exists when you have to leave your car unattended for a while, say in an airport car park. Having seen a BMW on bricks and wearing no wheels, I can safely suggest that if the wheel key had been in Spain or France with the car’s owner, the wheels and tyres would probably have been present when the car’s owner returned.

The locking of car wheels and tyres has been refined to the extent that corrosion and wheel balancing problems are a thing of the past. There are some cheap sets of locking wheel nuts/bolts on the market; these can fail even when used properly, so avoid them. Nevertheless, another question arises: what happens if you’ve lost the key to an unarguably tough locking wheel nut or bolt? One person on the Internet resorted to using a power hacksaw to dismantle the offending wheel and tyre. However, radical resection isn’t really necessary.  Car tyre fitters have generally encountered this problem before, and keep a range of tools, at least one specifically designed for this task.

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There’s nothing in the rule book that says you must keep the wheels your car had on when it arrived. Many people change their wheels, for a variety of reasons. Some want a different style of wheels, some want wider wheels and most want alloy wheels. A change of wheels usually means a change of car tyres. That is no problem in itself but there is a trap into which a lot of people have fallen with a resounding clatter.

The thing is, any car wheel will accept one or more different sizes of car tyre. There is, however, more to car wheels than just rim diameter and width. Ignore the other measurements or get them wrong and disaster looms. In short, you can find there’s a clash between your car tyres and its bodywork. This can happen with steering or suspension movement and often, it happens just the once, immedately before the tyre and bodywork wreck one another.

The first measurment is Pitch Circle Diameter, or PCD for short. This is nothing to do with car tyre to bodywork clearance but if you get this wrong, the wheels won’t fit. The PCD is the diameter of a circle drawn through the centre of your wheel mountings, be they studs or bolts. The wheels obviously need the right number of stud or bolt holes but you also need to ensure that the wheel nuts or bolts have the right thread and profile for your car’s hubs, and that they are correct for use with the wheels you’re using.

Now for the easy ones: rim width and diameter. You could go for the standard measurements here. However, many people want bigger wheels and low profile tyres. Fair enough – just ask the wheel supplier, who you can always blame if something doesn’t fit. It’s also important to make sure that the wheels can accommodate your brakes. Big wheels and low profile tyres were invented, in part at least, to allow for bigger brakes to be crammed in. These days, clearances are close and it’s problematic if your wheels and disc calipers rub each other. This makes only one difference to the car tyres: they won’t work too well if the wheels can’t rotate.

So, we come to the tricky one, the knotty problem of wheel offset. This is most easily understood with a little bit of theory. Imagine a car wheel sawn in half across its diameter. If you were to draw a line through the centre of the wheel rim, and this line was to coincide with the wheel’s hub mounting face, the wheel offset would be zero. If, as is common, the hub face lies outboard of the centre line, the wheel has positive offset. Conversely, if the hub face lies inboard of the centreline, the offset is negative. The degree of offset, apart from altering wheel clearance, has a profound effect on the behaviour of your car tyres.

Visually, positive offset places the car tyre further under the car’s wheelarch. Negative offset makes the tyre carcass sit further outboard. In either case, provided you don’t choose a seriously large figure in relation to what is standard, the car tyres won’t cause difficuties. That said, there is a danger in choosing too radical an offset, as this figure (usually expressed in millimetres) affects steering. You could find that your steering has becomes mysteriously heavy. Worse still, you could find it’s become over-light, to the extent that straight line driving becomes a thing of the past.

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‘We’re on your side.’ This sounds like the tag line in an advertisement but here it refers to the codes on a car tyre’s sidewall. Most of us know the obvious ones like those referring to wheel diameter and tyre section. There are, however, many other pieces of vital information to be found, moulded into the sidewall. Let’s consider some of the more important ones.

Did you know that some car tyres have a marked rating that indicates how well they handle heat build up? If you see a mysterious “A” on a tyre, it has the highest rating. A “C” denotes the lowest.

The traction rating shows how well a tyre can stop you on a wet road. This rating goes from “AA” to “CC”. No prizes for guessing which is the best.

Now for some numbers. Tread wear ratings go from 60 to 600 in increments of 20 and the figure shows how long the tyre is expected to last. In theory, a tyre marked “200″ should last twice as long as one marked “100″. This is, however, a relative rating. The actual tyre life will depend on many factors, including your driving style, the road surfaces encountered, correct wheel alignment and the right tyre pressure. Think ‘benchmark.’

The speed rating a tyre carries is extremely important. Using over-specified tyres is a (very expensive) upside here; tyres for high-speed use can be used at lower speeds. On the other hand, if the speed rating is too low and you have an accident, your insurance company may take a dim view of the tyres your car was wearing at the time. Speed ratings run from “L” (75 mph) to “Z” (150 + mph). Currently, H-rated tyres (130 mph) hold the largest percentage of new tyre sales.

So much for speed, what about load? Yes, car tyres tell you about the load they are capable of carrying, They have a marked load index (LI), which is valid for sub-130 mph speeds. Load indices range from 50 (190 Kg) to 169 (5,800 Kg) but the calculations are a touch complex. Let’s say you have a car that weighs 2 tonnes, or 2,000Kg. Divide this by four to get the weight on each wheel; this equals 500Kg. So far so good, but, do you know that all four wheels carry 500Kg or is one end of the car heavier than the other? In practice, it’s usual to add a percentage to cover such factors.

In our example, then, the car needs tyres with a load index of 84. We can add 20 percent, giving a weight bearing capacity of 600Kg. Therefore tyres with a load index of 90 will do very nicely. In reality, a car tyre’s load rating will exceed its actual needs by a long way. However, when speeds reach 130 mph or more, the load index calculations change dramatically. For reasons far to technical to explain here, the theoretical load rating decreases as road speed rises. In the event you run a very, very fast and heavy car where the speed cameras don’t work, there are experts in such matters. Find one!

Lastly, you should never use a tyre more than 6 years old. The date of manufacture is part of the DOT code marked on one sidewall. For example, a tyre marked “2709″ was made in the 27th week of 2009.

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Merityre.co.uk are one of the  leading UK independent suppliers of car tyres. Why not visit their website for an online tyre quote or contact your nearest fitting centre.