We may not view them for very long but movie star cars live on in our memories. Not all movies featuring memorable motors are car chases wrapped in sub-plots. That said, car tyres aren't just for these four-wheeled screen idols to sit on. Yes, rubber was burnt in many instances. The tyre-smoking heroes here have one thing in common – they're all from the 'States. So let's take a look across the pond at some US-born petrol-driven thespians.
The 1971 film 'Vanishing Point' is a classic car chase wrapped in celluloid. Starring Barry Newman and Cleavon Little (who went on to great things in 'Blazing Saddles'), Vanishing Point revolves around a fifteen-hour, transcontinental drive from Denver to San Francisco. The star car tyres doing the revolving in the film were fitted to a 1970 Dodge Challenger R/T, the suffix letters referring to 'road and track'. This 6.2-litre monster, driven by Erich Heuschele, developed the power of 375 gutsy, all-American horses. The car's F70x14 car tyres put the power onto the tarmac, with the aid of the Challenger's R/T package. Interestingly, the same model in the same colour popped up in Quentin Tarantino's 2007 movie 'Death Proof'. What's more, the Challenger's pedigree goes back in time. The black car driven by the baddies in 'Bullitt' was a 1968 Dodge Challenger 440 R/T.
More tyre-smoking Detroit iron finished in black starred in 1977's 'Smokey and the Bandit'. The motorised matinee idol here wasn't Burt Reynolds, it was a 1977 Pontiac Trans Am. This car's history can be traced – it stemmed from a General Motors Design show car created for GM design supremo Bill Mitchell. On this Trans Am, the car tyres were put under pressure in more than the literal sense. The car's 7.5 litre V8 motor became the last of the muscle car engines. Increasingly stringent emissions regulations in the US finally killed off these big V8 beasts in 1980. The stunt team on 'Smokey' pre-empted this, killing off, or at least damaging, all five film cars.
Now for something more unusual, though still in black paint. The next movie star was built using three Model T Ford bodies and a 133-inch hand made chassis. The Munsters Koach was created in 21 days in 1964, at a cost of $18,000; it took 500 hours to make its ornate steel scrollwork alone. Another big V8, by Ford this time, sent the power to the tyres via a four-speed manual gearbox, and the brass radiator and wings were hand formed. The Koach had ten Stromberg carburettors. On an eight cylinder engine? Not really. The visible carburettors were dummies, concealing two functioning four-barrel carbs.
In the Munsters, Grandpa, played by Al Lewis, became more than a little jealous of the Koach. So he acquired 'Drag-U-La'. This vehicle was notable for its spindly front tyres, mounted on Speedsport English buggy wire wheels. The V8 engine's 350 horsepower was transmitted to 11 inch-wide Firestone racing slick car tyres, mounted on specially made ten-inch deep Reynolds aluminum Rader drag wheels. Still more characteristic for a 'vampire', Drag-U-La's body shell was a coffin. The original Drag-U-La, one of four built, hangs from the ceiling in Planet Hollywood, Atlantic City, New Jersey.
Who was the talented creator of these last two oddities? The man responsible for putting a lot of tremendously memorable tinseltown tin on tyres. Yes, it was none other than Batmobile creator George Barris
Article Resource
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.
Thursday, 9 February 2012
Tuesday, 17 January 2012
Top Ten Car Tyre Tips
Car tyres don't generally ask too much of you. However, neglecting them can prove expensive and, in some circumstances, dangerous. These ten tips will enhance car tyre life, reduce your spending and perhaps save your life.
1. The wrong car tyre pressure is costly. Running on overinflated tyres accelerates wear and reduces both grip and ride comfort. Underinflated tyres also wear more quickly, and can worsen fuel economy by as much as ten percent. Check your tyre pressures regularly.
2. Cuts in car tyres are obvious. Lumps or bulges may be less so but they tend to indicate damage inside the car tyre's carcass. Check for any such damage while correcting tyre pressures. If in any doubt, avoid the risk of a blowout by having a tyre specialist examine the damage.
3. A spare wheel with a flat tyre is worse than useless. Check the spare tyre pressure regularly, unless you have run flat tyres or an onboard tyre pump and repair kit. Remember that space saver spare tyres generally have speed and distance restrictions.
4. If, at car tyre checking time, you find a stone embedded in a tyre tread, you can lever it out before it causes damage. However, if you find a nail in a tyre, leave it alone. The nail will be temporarily keeping the air in – have a tyre specialist take a look. He may be able to repair the tyre.
5. While using the tyre inflator at a garage, or a tyre pump at home, look after the tyre valve dust caps. They keep dirt and grit away from the delicate valves, and are a line of defence against tyre pressure loss. Always put them back carefully.
6. Potholes can damage more than your car tyres. Hit a large one hard enough and you could be facing a bill for the repair or replacement of one or more wheels. Should you be unlucky enough to encounter a big pothole and suspect damage has occurred, stop and examine the affected wheel(s) and tyre(s).
7. Never straddle a speed bump. Instead, let the wheels on one side of your car pass over the bump. This will prevent damage to your car's tyres, steering and suspension. When negotiating speed bumps and road-width speed pads, slow down or face the cost of repairs.
8. When you're manoeuvering, curb your enthusiasm so you don't kerb your car tyres. Kerb impacts can wreck not only tyres, they can scratch, chip and even dent your car's wheels. Steering misalignment can also result from kerbing.
9. Keep your car in a garage, if you can. Car tyres suffer from prolonged exposure to ultra violet light. This leads to cracking and crazing of the car tyre sidewalls' structure.
10. When the time to buy replacement tyres rolls around, think about replacing all four. Should this be too costly, always have new tyres fitted in pairs. It's accepted that the new tyres should be fitted to the rear wheels.
Article Resource
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.
1. The wrong car tyre pressure is costly. Running on overinflated tyres accelerates wear and reduces both grip and ride comfort. Underinflated tyres also wear more quickly, and can worsen fuel economy by as much as ten percent. Check your tyre pressures regularly.
2. Cuts in car tyres are obvious. Lumps or bulges may be less so but they tend to indicate damage inside the car tyre's carcass. Check for any such damage while correcting tyre pressures. If in any doubt, avoid the risk of a blowout by having a tyre specialist examine the damage.
3. A spare wheel with a flat tyre is worse than useless. Check the spare tyre pressure regularly, unless you have run flat tyres or an onboard tyre pump and repair kit. Remember that space saver spare tyres generally have speed and distance restrictions.
4. If, at car tyre checking time, you find a stone embedded in a tyre tread, you can lever it out before it causes damage. However, if you find a nail in a tyre, leave it alone. The nail will be temporarily keeping the air in – have a tyre specialist take a look. He may be able to repair the tyre.
5. While using the tyre inflator at a garage, or a tyre pump at home, look after the tyre valve dust caps. They keep dirt and grit away from the delicate valves, and are a line of defence against tyre pressure loss. Always put them back carefully.
6. Potholes can damage more than your car tyres. Hit a large one hard enough and you could be facing a bill for the repair or replacement of one or more wheels. Should you be unlucky enough to encounter a big pothole and suspect damage has occurred, stop and examine the affected wheel(s) and tyre(s).
7. Never straddle a speed bump. Instead, let the wheels on one side of your car pass over the bump. This will prevent damage to your car's tyres, steering and suspension. When negotiating speed bumps and road-width speed pads, slow down or face the cost of repairs.
8. When you're manoeuvering, curb your enthusiasm so you don't kerb your car tyres. Kerb impacts can wreck not only tyres, they can scratch, chip and even dent your car's wheels. Steering misalignment can also result from kerbing.
9. Keep your car in a garage, if you can. Car tyres suffer from prolonged exposure to ultra violet light. This leads to cracking and crazing of the car tyre sidewalls' structure.
10. When the time to buy replacement tyres rolls around, think about replacing all four. Should this be too costly, always have new tyres fitted in pairs. It's accepted that the new tyres should be fitted to the rear wheels.
Article Resource
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.
Winter Wisdom. Meeting Bad Weather Car Tyre Challenges
The usual seasonal symptoms are back again. In the UK, winter presents a series of tough tests for car tyres. As well as your tyres, it is you who are on test – drivers, rather than cars, generally cause accidents. Here are some salient points about winter driving…
Snow and Ice
A mountain climber's crampons, the tracks on a Caterpillar tractor, the toothed drive belt on a snowmobile…certain things are made to grip on snow and ice. Since (with some exceptions) you can't fit such things on your car, you have to cope, using the tyres your car usually wears. There is, however an option. When the temperature drops, your usual tyres will lose flexibility. Winter car tyres are designed to retain their flexibility at lower temperatures, so it makes sense to invest in a set. Motorists are discovering that such car tyres really do offer significantly enhanced grip and control, and using them on a set of (preferably steel) 'winter wheels' will preserve your usual alloy wheels from the ravages of salt and grit.
What are the exceptions? Countries with permafrost can be home to car tyres with studs. In the UK, seriously bad conditions can trigger the use of snow chains. A new item occupies the middle ground. Snow socks are car tyre covers made of a tough, woven material. Easier to fit and quieter than chains, they can be useful when drivers are caught out by unexpected snowfalls. Bear in mind that they will wear out in no time on tarmac.
Rain
When it isn't quite cold enough to snow, rain and sleet present car tyre challenges of their own. Reduced visibility is a foregone conclusion but don't forget that wet weather compromises grip. Your car tyres will move surface water but a wet surface remains relatively slippery. Remember to leave more room between you and the vehicle in front, to allow for increased braking distances.
Flooding
Lots of rain can lead to flooding. Standing water can be dangerous. When your car tyres hit it, you'll feel the steering wheel pulling in response. At worst, your tyres may aquaplane. When the tyres ride on the surface of the water, suspiciously light steering signals radically reduced grip. If you feel this, lift off the throttle and slow down until the grip returns.
If you encounter a flood, remember that negotiating it requires care. Keep to the crown of the road, where the water will be shallower, and look out for the white line. This will help you gauge the depth of the water. While you can trust your tyres, remember that your engine, if it sucks in water, will be wrecked. Keep the engine revs up to help stop the exhaust inhaling water. However, if you are in any doubt whatsoever about the depth of the water, use another route.
Fog
In thick fog, you're bound to suffer loss of visibility. Your car tyres won't suddenly offer greater grip just because you notice that you're hurtling towards the back of stationary truck. So drive as fast as you can see, and no faster. Remember to use your windscreen wipers and washers often in fog; your screen can collect water and grime surprisingly quickly, further reducing visibility.
In winter, the watchword is caution. Even on winter car tyres, grip will be compromised to some extent by bad weather. Should the visibility and grip be truly awful, simply put your feet up by the fire and live to drive another day.
Article Resource
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.
Snow and Ice
A mountain climber's crampons, the tracks on a Caterpillar tractor, the toothed drive belt on a snowmobile…certain things are made to grip on snow and ice. Since (with some exceptions) you can't fit such things on your car, you have to cope, using the tyres your car usually wears. There is, however an option. When the temperature drops, your usual tyres will lose flexibility. Winter car tyres are designed to retain their flexibility at lower temperatures, so it makes sense to invest in a set. Motorists are discovering that such car tyres really do offer significantly enhanced grip and control, and using them on a set of (preferably steel) 'winter wheels' will preserve your usual alloy wheels from the ravages of salt and grit.
What are the exceptions? Countries with permafrost can be home to car tyres with studs. In the UK, seriously bad conditions can trigger the use of snow chains. A new item occupies the middle ground. Snow socks are car tyre covers made of a tough, woven material. Easier to fit and quieter than chains, they can be useful when drivers are caught out by unexpected snowfalls. Bear in mind that they will wear out in no time on tarmac.
Rain
When it isn't quite cold enough to snow, rain and sleet present car tyre challenges of their own. Reduced visibility is a foregone conclusion but don't forget that wet weather compromises grip. Your car tyres will move surface water but a wet surface remains relatively slippery. Remember to leave more room between you and the vehicle in front, to allow for increased braking distances.
Flooding
Lots of rain can lead to flooding. Standing water can be dangerous. When your car tyres hit it, you'll feel the steering wheel pulling in response. At worst, your tyres may aquaplane. When the tyres ride on the surface of the water, suspiciously light steering signals radically reduced grip. If you feel this, lift off the throttle and slow down until the grip returns.
If you encounter a flood, remember that negotiating it requires care. Keep to the crown of the road, where the water will be shallower, and look out for the white line. This will help you gauge the depth of the water. While you can trust your tyres, remember that your engine, if it sucks in water, will be wrecked. Keep the engine revs up to help stop the exhaust inhaling water. However, if you are in any doubt whatsoever about the depth of the water, use another route.
Fog
In thick fog, you're bound to suffer loss of visibility. Your car tyres won't suddenly offer greater grip just because you notice that you're hurtling towards the back of stationary truck. So drive as fast as you can see, and no faster. Remember to use your windscreen wipers and washers often in fog; your screen can collect water and grime surprisingly quickly, further reducing visibility.
In winter, the watchword is caution. Even on winter car tyres, grip will be compromised to some extent by bad weather. Should the visibility and grip be truly awful, simply put your feet up by the fire and live to drive another day.
Article Resource
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.
Wednesday, 21 December 2011
The Thin Black Line. Car Tyre Grip is Tread-Dependent
Here's a sobering thought. Summer or winter, rain or shine, all that lies between you and a short, damaging trip into the scenery is the equivalent of the area of four shoe soles. Yes, every car tyre has a 'contact patch' the amount of its treaded area that touches the road. This area is only the size of an adult's footprint.
Let's say your car weighs one tonne. Nobody weighs half a tonne and the soles of his or her shoes do a pretty good job, expect perhaps on ice or snow. Translated into car tyre terms, the four-sole area has to do much, much more. It's unlikely, for example, that a road car could generate a cornering force of 1g. Under heavy braking, it's quite possible for such a force to be generated. Moreover, the forces generated during acceleration and cornering can be very high. Your car tyres and their contact patches do more than a 'pretty good job'. You don't usually expect your shoes to keep you from slipping in adverse conditions, such as on gritty or diesel-soaked tarmac in extremes of temperature. Your car tyres do this on a regular basis.
Legally, each of your car tyres must have a minimum of 1.6 millimetres of tread across ¾ of the width of the tyre's running surface. Not meeting this requirement can get you three penalty points on your licence, as well as a £2,500 fine…per tyre. So, four balding car tyres equals a lost licence and fines of up to £10,000.
In this context, the law could be called an ass. Why? Because just 1.6 millimetres of tread on a car tyre is cutting things fine when it comes to grip. The Royal Society for the Prevention of Accidents (RoSpa) put this to the test. They tried some emergency stops in a typical car on some typical surfaces. On smooth concrete, as some motorway stretches have, the car's barely legal tyres took a distance of 46.6 percent more to stop than an equivalent car with good tyres. Similarly, on hot rolled asphalt, the worn tyres needed 36.8 percent more distance to bring the car to a halt. There's no need to ask why RoSpa recommends a minimum tread depth of 3 millimetres.
This isn't the only scenario where worn car tyres will struggle. Tyres are designed to act like water pumps in wet conditions, they can clear surface water from their contact patches. When this fails to happen properly, the tyre will ride on a thin film of water. If this happens, you'd feel the steering lighten, which is an indicator of what's actually going on. When a car tyre is unable to cut through road water fast enough, it will aquaplane. Aquaplaning equals significantly reduced grip, as you might find out when you attempt to steer or brake.
Whilst it may seem to make sense to get the very most out of the treads on your car tyres, there is such a thing as false economy. Your car tyres have wear indicators, moulded into the treads. Take a look at them and, if the treads no longer stand proud of the tread wear indicators, it's new tyre time. Running your tyres down to the legal minimum could cost you far more than you think.
Article Resource
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.
Let's say your car weighs one tonne. Nobody weighs half a tonne and the soles of his or her shoes do a pretty good job, expect perhaps on ice or snow. Translated into car tyre terms, the four-sole area has to do much, much more. It's unlikely, for example, that a road car could generate a cornering force of 1g. Under heavy braking, it's quite possible for such a force to be generated. Moreover, the forces generated during acceleration and cornering can be very high. Your car tyres and their contact patches do more than a 'pretty good job'. You don't usually expect your shoes to keep you from slipping in adverse conditions, such as on gritty or diesel-soaked tarmac in extremes of temperature. Your car tyres do this on a regular basis.
Legally, each of your car tyres must have a minimum of 1.6 millimetres of tread across ¾ of the width of the tyre's running surface. Not meeting this requirement can get you three penalty points on your licence, as well as a £2,500 fine…per tyre. So, four balding car tyres equals a lost licence and fines of up to £10,000.
In this context, the law could be called an ass. Why? Because just 1.6 millimetres of tread on a car tyre is cutting things fine when it comes to grip. The Royal Society for the Prevention of Accidents (RoSpa) put this to the test. They tried some emergency stops in a typical car on some typical surfaces. On smooth concrete, as some motorway stretches have, the car's barely legal tyres took a distance of 46.6 percent more to stop than an equivalent car with good tyres. Similarly, on hot rolled asphalt, the worn tyres needed 36.8 percent more distance to bring the car to a halt. There's no need to ask why RoSpa recommends a minimum tread depth of 3 millimetres.
This isn't the only scenario where worn car tyres will struggle. Tyres are designed to act like water pumps in wet conditions, they can clear surface water from their contact patches. When this fails to happen properly, the tyre will ride on a thin film of water. If this happens, you'd feel the steering lighten, which is an indicator of what's actually going on. When a car tyre is unable to cut through road water fast enough, it will aquaplane. Aquaplaning equals significantly reduced grip, as you might find out when you attempt to steer or brake.
Whilst it may seem to make sense to get the very most out of the treads on your car tyres, there is such a thing as false economy. Your car tyres have wear indicators, moulded into the treads. Take a look at them and, if the treads no longer stand proud of the tread wear indicators, it's new tyre time. Running your tyres down to the legal minimum could cost you far more than you think.
Article Resource
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.
For Your Tyre Treads' Sake. Wheel Alignment
Wheel alignment? Surely your car's wheels are in line all the time? In fact, they aren't necessarily. Speed bumps, kerbing, speed pads and general wear and tear on a car's suspension and steering can put the wheels out of alignment. Misalignment may be felt as pulling to one side or another, and/or strange steering. In the longer term, your car tyres will suffer – bad wheel alignment can radically reduce tyre life.
So, how do you fix poor wheel alignment, thus making your car steer and brake better, as well as achieving maximum car tyre life? The good news is that car manufacturers provide a means of adjusting wheel alignment. The not so bad news is that you can't correct poor alignment yourself.
Cue a visit to your local friendly tyre man. Good tyre bays (and garages) have the equipment to check and adjust wheel alignment. All you have to do is watch (or not, depending on your preference) and pay for the work. Then, drive away secure in the knowledge that your car is shipshape in the wheel alignment department.
What happens in a wheel alignment session? Generally, three things are checked, and adjusted as necessary. The first check establishes that the car tyres are vertical, as viewed from the front or rear. Sometimes, the tyres may not be truly vertical. Some cars' tyres sit at a slight angle from the perpendicular. This is the camber angle, which can be adjusted to meet the car maker's specification.
The second check involves another angle, the castor angle. Does your car run on castors? Technically, yes, the castor angle permits the wheels and tyres to return to straight ahead when the car is rolling with no steering input. As you know, your front wheels turn from side to side in response to your turning the steering wheel. No matter how the wheels and tyres pivot, a line drawn through the centre of the axis on which they pivot won't be vertical. The line has to lean backwards slightly and if it doesn't, the steering will feel very odd. Again, this can be cured by adjustment.
The last check is on a figure called the 'toe'. All car suspension has a small degree of flexibility built into it. So, if the car tyres are parallel at rest, the drag between them and the road as the car moves would cause this flexibility to allow the wheels to splay very slightly. You wouldn't see this but your tyres would soon tell you all about it, by wearing out the inner edges of their treads. So, the wheels are usually set to 'toe-in', so they run parallel. If the tyres toe out, if the toe-in is too much or if the toe angle varies from side to side, the car tyres will wear out prematurely. Curing this is again a matter of adjustment.
Wheel alignment used to be checked with a special gauge that used a mirror and lens system. Nowadays, it's common for car tyre bays and garages to measure the angles involved using laser equipment. Yes, accurate measurement is necessary. In some instances, worn suspension or steering components mean that a problem can't be adjusted away. Then, the tyre man in question will tell you what needs repairing or replacing for accurate alignment to be achieved. It's also the case, especially on a car with independent rear suspension, for the rear wheels and tyres to be misaligned. Once again, adjustment is usually possible.
Is it possible to stop your car's wheels becoming misaligned and making the tyres suffer? In a word, yes. Don't kerb your car tyres. Avoid potholes and traverse speed pads carefully. Above all, always negotiate speed bumps with the tyres on one side of your car. Straddling speed bumps is a major cause of both wheel misalignment and tyre carcass damage. You have been warned!
Article Resource
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.
So, how do you fix poor wheel alignment, thus making your car steer and brake better, as well as achieving maximum car tyre life? The good news is that car manufacturers provide a means of adjusting wheel alignment. The not so bad news is that you can't correct poor alignment yourself.
Cue a visit to your local friendly tyre man. Good tyre bays (and garages) have the equipment to check and adjust wheel alignment. All you have to do is watch (or not, depending on your preference) and pay for the work. Then, drive away secure in the knowledge that your car is shipshape in the wheel alignment department.
What happens in a wheel alignment session? Generally, three things are checked, and adjusted as necessary. The first check establishes that the car tyres are vertical, as viewed from the front or rear. Sometimes, the tyres may not be truly vertical. Some cars' tyres sit at a slight angle from the perpendicular. This is the camber angle, which can be adjusted to meet the car maker's specification.
The second check involves another angle, the castor angle. Does your car run on castors? Technically, yes, the castor angle permits the wheels and tyres to return to straight ahead when the car is rolling with no steering input. As you know, your front wheels turn from side to side in response to your turning the steering wheel. No matter how the wheels and tyres pivot, a line drawn through the centre of the axis on which they pivot won't be vertical. The line has to lean backwards slightly and if it doesn't, the steering will feel very odd. Again, this can be cured by adjustment.
The last check is on a figure called the 'toe'. All car suspension has a small degree of flexibility built into it. So, if the car tyres are parallel at rest, the drag between them and the road as the car moves would cause this flexibility to allow the wheels to splay very slightly. You wouldn't see this but your tyres would soon tell you all about it, by wearing out the inner edges of their treads. So, the wheels are usually set to 'toe-in', so they run parallel. If the tyres toe out, if the toe-in is too much or if the toe angle varies from side to side, the car tyres will wear out prematurely. Curing this is again a matter of adjustment.
Wheel alignment used to be checked with a special gauge that used a mirror and lens system. Nowadays, it's common for car tyre bays and garages to measure the angles involved using laser equipment. Yes, accurate measurement is necessary. In some instances, worn suspension or steering components mean that a problem can't be adjusted away. Then, the tyre man in question will tell you what needs repairing or replacing for accurate alignment to be achieved. It's also the case, especially on a car with independent rear suspension, for the rear wheels and tyres to be misaligned. Once again, adjustment is usually possible.
Is it possible to stop your car's wheels becoming misaligned and making the tyres suffer? In a word, yes. Don't kerb your car tyres. Avoid potholes and traverse speed pads carefully. Above all, always negotiate speed bumps with the tyres on one side of your car. Straddling speed bumps is a major cause of both wheel misalignment and tyre carcass damage. You have been warned!
Article Resource
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.
Monday, 7 November 2011
A Bit on the Sidewall – What Car Tyre Markings Mean
All car tyres have them but not everyone knows what the markings moulded in a tyre's sidewall means. At the very least, it is necessary on many cars to check the sidewall as the tyre pressure to be used can relate to the tyre size. However, this little trip through the meaning of the markings will inform, especially when the time to buy new tyres arrives.
Here, we can use a theoretical, typical car tyre. Let's say it's marked 185/55R13 91 H. Confused already? Don't be, things will become perfectly clear! Take the tyre markings one by one….
185 – This is the width of the tyre’s section in millimetres, i.e. the width of the carcass of the tyre, not its tread's width. 185 millimetres is a little over seven and a quarter inches.
55 – This figure refers to the tyre’s aspect ratio, which is the height of the tyre height expressed as a percentage of its width. 55 is a low-ish profile but aspect ratios can go as low as 30%. Low profile car tyres grip well and deform little but the cost is reduced ride comfort and poor protection against potholes, kerbs and road debris.
R – This couldn't be simpler. Here, R means radial.
13 – This number refers to the diameter of wheel the tyre will fit. Why this is expressed in inches rather than millimetres isn't clear but it is standard practice.
91 – This is the tyre load index, a code for the maximum load capacity of the tyre when driven at its maximum rated speed. The figure 91 means a rating of 615 kilograms.
H – This final marking shows the tyre’s speed rating. This H rating means the tyre can cope with extended use at a maximum speed of 130 miles per hour (210 kilometres per hour). The highest possible speed rating is Z. Car tyres thus marked are capable of maintaining 150 mph (240 kph).
There are numerous other markings on a car tyre's sidewall, some of which are for the tyre fitter's information. For example, if the tyre has a specific direction of rotation, there will be an arrow. A 'TWI' marking denotes where the tread wear indicator(s) are moulded into the tyre's tread. A coloured dot will show the tyre fitter where the tyre casing should sit on the wheel in relation to the valve. There will also be ECE (not EEC) type approval markings, possibly special construction markings, such as M&S (Mud and Snow), and a maximum pressure marking.
One marking that could be of interest to you is the DOT code. The last four numbers in this show the tyre’s date of manufacture. Four-digit codes began after 2003 so if your new car tyre has the code 2 5 0 9, it was made in the 30th week of 2009. Tyres over 6 years old must never be used.
All very interesting but do these markings matter to you? Apart from the aforementioned tyre size vs. tyre pressure element, the speed and load ratings are extremely important. Why? Because at best, using under-specified tyres is illegal and can invalidate your car insurance. At worst, the wrong kind of tyre can fail and cause a potentially lethal accident at high speed.
Article Resource
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.
Here, we can use a theoretical, typical car tyre. Let's say it's marked 185/55R13 91 H. Confused already? Don't be, things will become perfectly clear! Take the tyre markings one by one….
185 – This is the width of the tyre’s section in millimetres, i.e. the width of the carcass of the tyre, not its tread's width. 185 millimetres is a little over seven and a quarter inches.
55 – This figure refers to the tyre’s aspect ratio, which is the height of the tyre height expressed as a percentage of its width. 55 is a low-ish profile but aspect ratios can go as low as 30%. Low profile car tyres grip well and deform little but the cost is reduced ride comfort and poor protection against potholes, kerbs and road debris.
R – This couldn't be simpler. Here, R means radial.
13 – This number refers to the diameter of wheel the tyre will fit. Why this is expressed in inches rather than millimetres isn't clear but it is standard practice.
91 – This is the tyre load index, a code for the maximum load capacity of the tyre when driven at its maximum rated speed. The figure 91 means a rating of 615 kilograms.
H – This final marking shows the tyre’s speed rating. This H rating means the tyre can cope with extended use at a maximum speed of 130 miles per hour (210 kilometres per hour). The highest possible speed rating is Z. Car tyres thus marked are capable of maintaining 150 mph (240 kph).
There are numerous other markings on a car tyre's sidewall, some of which are for the tyre fitter's information. For example, if the tyre has a specific direction of rotation, there will be an arrow. A 'TWI' marking denotes where the tread wear indicator(s) are moulded into the tyre's tread. A coloured dot will show the tyre fitter where the tyre casing should sit on the wheel in relation to the valve. There will also be ECE (not EEC) type approval markings, possibly special construction markings, such as M&S (Mud and Snow), and a maximum pressure marking.
One marking that could be of interest to you is the DOT code. The last four numbers in this show the tyre’s date of manufacture. Four-digit codes began after 2003 so if your new car tyre has the code 2 5 0 9, it was made in the 30th week of 2009. Tyres over 6 years old must never be used.
All very interesting but do these markings matter to you? Apart from the aforementioned tyre size vs. tyre pressure element, the speed and load ratings are extremely important. Why? Because at best, using under-specified tyres is illegal and can invalidate your car insurance. At worst, the wrong kind of tyre can fail and cause a potentially lethal accident at high speed.
Article Resource
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.
Winter of Discontent…Beat it with Winter Tyres
Last night's frost warning was a harbinger of the approach of winter. Here in the UK, we should be used to harsh conditions. However, give us an inch (of snow) and the miles aren't covered…the country tends to come to a grinding halt. Is there a solution? Well, the increasingly popular winter car tyres may help.
This begs a question: are winter tyres genuinely useful or are they just a way of extracting more money from we motorists? Let's see.
Recommended in Andorra, Italy, Norway and Switzerland, winter tyres are compulsory in Austria, Germany and Sweden and mandatory in Finland. These rules naturally apply on snow-covered roads and/or during the snow season. Often, there is the distinction that the tyres must be marked 'M&S' (no, not Marks and Spencer, the marking stands for 'Mud and Snow'.) Newer snow tyres may have a symbol of a snowflake in front of a mountain. Currently, the distinction between winter and snow tyres is a touch unclear. A good tyre bay will advise you of the exact designation and specification.
In fact, specification is what winter tyres are all about. Car tyres in general are made in much the same way but the rubber compounds used and the tread patterns vary. Winter tyres are made with a high silica content. The probable tread pattern has two tricks up its sleeve. One is a more aggressive tread pattern than 'summer' car tyres. This is present to enhance grip.
The winter car tyre tread's second line of defence involves a winter tyre key word, flexibility. When ordinary tyres have to work in temperatures below 7 degrees centigrade, they stiffen up in the cold conditions. In winter tyres, the compound and tread pattern both improve flexibility.
The benefit of winter tyres is that they give better grip in cold conditions, in rain as well as when snow and ice are about. There are plenty of subjective reports concerning car tyres and most of those concerning winter tyres are favourable. In some cases, cars found to be pretty hopeless in snow are transformed!
Are winter tyres the car tyres for all seasons? Their name offers a huge clue here. Summer tyres will outperform winter ones on dry roads and in reasonable temperatures, and winter tyres, having a softer compound, will naturally wear faster. This suggests following the lead of many continental drivers. They have two sets of tyres, one for winter, one for summer.
This brings us, in turn, to a potentially superior arrangement, which is also popular on the continent and in some cases is a legal requirement. Generally speaking, car tyres can handle most road conditions. However, in the depths of winter, the environment down at road level can be especially harsh. Car tyres may be able to cope with the salt and grit that gives some winter grip but our alloy wheels can suffer. Many popular cars have base models that wear steel wheels. One solution is to have a set of winter tyres on these. A set of steel wheels, with winter tyres, balanced and ready to roll can be fitted when the thermometer starts to plummet. With these 'winter wheels' fitted, your car can take on whatever the season has to throw at it, while your pristine summer wheels can live in cool, dark storage, ready for Spring. Bear in mind that suitable wheel nuts/bolts will have to be factored into the equation.
What's the bottom line? Assuming you need to use your car in the off season, winter car tyres are worth the investment.
Article Resource
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.
This begs a question: are winter tyres genuinely useful or are they just a way of extracting more money from we motorists? Let's see.
Recommended in Andorra, Italy, Norway and Switzerland, winter tyres are compulsory in Austria, Germany and Sweden and mandatory in Finland. These rules naturally apply on snow-covered roads and/or during the snow season. Often, there is the distinction that the tyres must be marked 'M&S' (no, not Marks and Spencer, the marking stands for 'Mud and Snow'.) Newer snow tyres may have a symbol of a snowflake in front of a mountain. Currently, the distinction between winter and snow tyres is a touch unclear. A good tyre bay will advise you of the exact designation and specification.
In fact, specification is what winter tyres are all about. Car tyres in general are made in much the same way but the rubber compounds used and the tread patterns vary. Winter tyres are made with a high silica content. The probable tread pattern has two tricks up its sleeve. One is a more aggressive tread pattern than 'summer' car tyres. This is present to enhance grip.
The winter car tyre tread's second line of defence involves a winter tyre key word, flexibility. When ordinary tyres have to work in temperatures below 7 degrees centigrade, they stiffen up in the cold conditions. In winter tyres, the compound and tread pattern both improve flexibility.
The benefit of winter tyres is that they give better grip in cold conditions, in rain as well as when snow and ice are about. There are plenty of subjective reports concerning car tyres and most of those concerning winter tyres are favourable. In some cases, cars found to be pretty hopeless in snow are transformed!
Are winter tyres the car tyres for all seasons? Their name offers a huge clue here. Summer tyres will outperform winter ones on dry roads and in reasonable temperatures, and winter tyres, having a softer compound, will naturally wear faster. This suggests following the lead of many continental drivers. They have two sets of tyres, one for winter, one for summer.
This brings us, in turn, to a potentially superior arrangement, which is also popular on the continent and in some cases is a legal requirement. Generally speaking, car tyres can handle most road conditions. However, in the depths of winter, the environment down at road level can be especially harsh. Car tyres may be able to cope with the salt and grit that gives some winter grip but our alloy wheels can suffer. Many popular cars have base models that wear steel wheels. One solution is to have a set of winter tyres on these. A set of steel wheels, with winter tyres, balanced and ready to roll can be fitted when the thermometer starts to plummet. With these 'winter wheels' fitted, your car can take on whatever the season has to throw at it, while your pristine summer wheels can live in cool, dark storage, ready for Spring. Bear in mind that suitable wheel nuts/bolts will have to be factored into the equation.
What's the bottom line? Assuming you need to use your car in the off season, winter car tyres are worth the investment.
Article Resource
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.
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