Automotive

Lines on New Tires

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  • Dec 6th, 2013 5:30 pm
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[OP]
Deal Expert
Mar 25, 2005
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Lines on New Tires

This is something that I have never been able to figure out, so I thought Id ask. When ever I see a new car/new tire, there are always a few lines on it. They are normally white, red, and blue I believe. Is there any reason for this?
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Deal Addict
Dec 28, 2005
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Image

like those blue lines? probably used to ensure even tread depth throughout? meh who gives haha
[OP]
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Mar 25, 2005
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Those are the lines! Cant seem to figure them out.
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Jan 5, 2006
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Kasakato wrote:
Apr 22nd, 2008 11:47 pm
Those are the lines! Cant seem to figure them out.
Maybe so people can't return the tires after actually using them? I really don't know; just a guess.
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Jul 10, 2007
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+1 with Asad.

Probably just an indication that the tires are new... also the colours cold be used as some sort of organizational colour-coding system for brands/sizes etc.
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#KeepFightingMichael
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Jul 22, 2005
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No, that's not what they are used for.

When the tires are new, and in the Manuafturers warehouse, they lie flat (stacked) like in the picture. Different colors represent different sizes.

Because the tires are sideways, you can't always read the size (even the font on the sticker is hard to read from a distance). Therefore they are color coded.
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Jul 7, 2005
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Scarborough
but there are like hundreds of differnt possible tire sizes? they got a different colour for each one?
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Mar 12, 2005
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^ i think he's talking about rim size?
14", 15", 16", etc

just a guess
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Nov 11, 2006
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Tdot
i got those annoying YELLOW dots on my new tires sidewall...anyone know y its there?
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May 7, 2006
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Excellent question and for your reading enjoyment:

Coloured dots and stripes - whats that all about?
When you're looking for new tyres, you'll often see some coloured dots on the tyre sidewall, and bands of colour in the tread. These are all here for a reason, but it's more for the tyre fitter than for your benefit.
The dots on the sidewall typically denote unformity and weight. It's impossible to manufacture a tyre which is perfectly balanced and perfectly manufactured in the belts. As a result, all tyres have a point on the tread which is lighter than the rest of the tyre - a thin spot if you like. It's fractional - you'd never notice it unless you used tyre manufacturing equipment to find it, but its there. When the tyre is manufactured, this point is found and a coloured dot is put on the sidewall of the tyre corresponding to the light spot.
Typically this is a yellow dot (although some manufacturers use different colours just to confuse us) and is known as the weight mark. Typically the yellow dot should end up aligned to the valve stem on your wheel and tyre combo. This is because you can help minimize the amount of weight needed to balance the tyre and wheel combo by mounting the tire so that its light point is matched up with the wheel's heavy balance point. Every wheel has a valve stem which cannot be moved so that is considered to be the
heavy balance point for the wheel.
As well as not being able to manufacture perfectly weighted tyres, it's also nearly impossible to make a tyre which is perfectly circular. By perfectly circular, I mean down to some nauseating number of decimal places. Again, you'd be hard pushed to actually be able to tell that a tyre wasn't round without specialist equipment. Every tyre has a high and a low spot, the difference of which is called radial runout. Using sophisticated computer analysis, tyre manufacturers spin each tyre and look for the 'wobble' in the tyre at certain RPMs. It's all about harmonic frequency (you know - the frequency at which something vibrates, like the Tacoma Narrows
bridge collapse). Where the first harmonic curve from the tyre wobble hits its high point, that's where the tyre's high spot is.
Manufacturers typically mark this point with a red dot on the tyre sidewall, although again, some tyres have no marks, and others use different colours. This is called the uniformity mark. Correspondingly, most wheel rims are also not 100% circular, and will have a notch or a dimple stamped into the wheel rim somewhere indicating their low point. It makes sense then, that the high point of the tyre should be matched with the low point of the wheel rim to balance out the radial runout.


What about the coloured stripes in the tread?
Often when you buy tyres, there will be a coloured band or stripe running around the tyre inside the tread. These can be any colour and can be placed laterally almost anyhwere across the tread. Some are on the tread blocks whilst others are on the tyre carcass.
For ages I thought this was a uniformity check - a painted mark used to check the "roundness" of the tyre. But I had a tyre dealer contact me with a far more feasible answer. The same tyre is often made with slightly tweaked specifications for different vehicles.
To easily identify these same labelled tyres when they are warehoused or in storage, different markings and stripes are used.
Sometimes stripes are added for huge bulk orders to various manufactures. Eg All the red outside stripes are for Toyota next week.This gives anyone in the warehouse a very quick visual check of the different types of tyres without needing to pull them all down and read the sidewall on each one.
As well as the colour, the actual position of the lines is something to take note of too. They're a measure of something called runout. Depending on how the belts are laid on the tyre during manufacturing, they can cause the tire to "run out" - to not track perfectly straight, but pull to the left or right. The closer to the centre of the tyre that these lines are, the less runout the tyre has and the straighter it will track when mounted on your car. So for example, if you were looking at your car from the front and you saw the coloured striped running around the right side of both your front tyres, the car would likely have a tendency to pull to that side. The best thing is to have the coloured stripes on opposite sides of the tyres for opposite sides of the car, so that the runout on each side will counteract the other and help maintain a good straight running. This is something that not many tyre fitting places know about or take any notice of. The obvious solution to having the stripes both on one side is to flip one of the tyres around, but that will only work if they're not unidirectional tyres. If they are unidirectional (and thus must be mounted to rotate a specific way) then you should try to find another tyre from the same batch with the stripe on the opposite side.
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Jul 22, 2005
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majesus wrote:
Apr 23rd, 2008 7:51 pm

Coloured dots and stripes - whats that all about? It makes sense then, that the high point of the tyre should be matched with the low point of the wheel rim to balance out the radial runout.
This is absolutely true, however, it should be noted that since we live in a modern age, where the tire/wheel combo is put on a computerized balancer that dynamically balances the combo, this step is often ignored and is not necessary. However, it is necessary if you don't balance the tire (but who does that nowadays), or use such methods like balancing sand or the bubble balancer (again, who does that nowadays).

majesus wrote:
Apr 23rd, 2008 7:51 pm
What about the coloured stripes in the tread?
As well as the colour, the actual position of the lines is something to take note of too. They're a measure of something called runout. Depending on how the belts are laid on the tyre during manufacturing, they can cause the tire to "run out" - to not track perfectly straight, but pull to the left or right. The closer to the centre of the tyre that these lines are, the less runout the tyre has and the straighter it will track when mounted on your car. So for example, if you were looking at your car from the front and you saw the coloured striped running around the right side of both your front tyres, the car would likely have a tendency to pull to that side.
I find this not to be true. I've balanced perfect straight (non wobbly) tires on a laser balancer, and yet as the tire spins, the lines will be all over the place. The laser balacer is very accurate and shows the actual runout amount.
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Jun 21, 2005
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Richmond Hill
Very interesting read. Thanks!
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Apr 5, 2007
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GTA
majesus wrote:
Apr 23rd, 2008 7:51 pm
Excellent question and for your reading enjoyment:

Coloured dots and stripes - whats that all about?
When you're looking for new tyres, you'll often see some coloured dots on the tyre sidewall, and bands of colour in the tread. These are all here for a reason, but it's more for the tyre fitter than for your benefit.
The dots on the sidewall typically denote unformity and weight. It's impossible to manufacture a tyre which is perfectly balanced and perfectly manufactured in the belts. As a result, all tyres have a point on the tread which is lighter than the rest of the tyre - a thin spot if you like. It's fractional - you'd never notice it unless you used tyre manufacturing equipment to find it, but its there. When the tyre is manufactured, this point is found and a coloured dot is put on the sidewall of the tyre corresponding to the light spot.
Typically this is a yellow dot (although some manufacturers use different colours just to confuse us) and is known as the weight mark. Typically the yellow dot should end up aligned to the valve stem on your wheel and tyre combo. This is because you can help minimize the amount of weight needed to balance the tyre and wheel combo by mounting the tire so that its light point is matched up with the wheel's heavy balance point. Every wheel has a valve stem which cannot be moved so that is considered to be the
heavy balance point for the wheel.
As well as not being able to manufacture perfectly weighted tyres, it's also nearly impossible to make a tyre which is perfectly circular. By perfectly circular, I mean down to some nauseating number of decimal places. Again, you'd be hard pushed to actually be able to tell that a tyre wasn't round without specialist equipment. Every tyre has a high and a low spot, the difference of which is called radial runout. Using sophisticated computer analysis, tyre manufacturers spin each tyre and look for the 'wobble' in the tyre at certain RPMs. It's all about harmonic frequency (you know - the frequency at which something vibrates, like the Tacoma Narrows
bridge collapse). Where the first harmonic curve from the tyre wobble hits its high point, that's where the tyre's high spot is.
Manufacturers typically mark this point with a red dot on the tyre sidewall, although again, some tyres have no marks, and others use different colours. This is called the uniformity mark. Correspondingly, most wheel rims are also not 100% circular, and will have a notch or a dimple stamped into the wheel rim somewhere indicating their low point. It makes sense then, that the high point of the tyre should be matched with the low point of the wheel rim to balance out the radial runout.


What about the coloured stripes in the tread?
Often when you buy tyres, there will be a coloured band or stripe running around the tyre inside the tread. These can be any colour and can be placed laterally almost anyhwere across the tread. Some are on the tread blocks whilst others are on the tyre carcass.
For ages I thought this was a uniformity check - a painted mark used to check the "roundness" of the tyre. But I had a tyre dealer contact me with a far more feasible answer. The same tyre is often made with slightly tweaked specifications for different vehicles.
To easily identify these same labelled tyres when they are warehoused or in storage, different markings and stripes are used.
Sometimes stripes are added for huge bulk orders to various manufactures. Eg All the red outside stripes are for Toyota next week.This gives anyone in the warehouse a very quick visual check of the different types of tyres without needing to pull them all down and read the sidewall on each one.
As well as the colour, the actual position of the lines is something to take note of too. They're a measure of something called runout. Depending on how the belts are laid on the tyre during manufacturing, they can cause the tire to "run out" - to not track perfectly straight, but pull to the left or right. The closer to the centre of the tyre that these lines are, the less runout the tyre has and the straighter it will track when mounted on your car. So for example, if you were looking at your car from the front and you saw the coloured striped running around the right side of both your front tyres, the car would likely have a tendency to pull to that side. The best thing is to have the coloured stripes on opposite sides of the tyres for opposite sides of the car, so that the runout on each side will counteract the other and help maintain a good straight running. This is something that not many tyre fitting places know about or take any notice of. The obvious solution to having the stripes both on one side is to flip one of the tyres around, but that will only work if they're not unidirectional tyres. If they are unidirectional (and thus must be mounted to rotate a specific way) then you should try to find another tyre from the same batch with the stripe on the opposite side.
Helpful!
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Dec 11, 2004
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CRXGSR wrote:
Apr 26th, 2008 5:51 am
This is absolutely true, however, it should be noted that since we live in a modern age, where the tire/wheel combo is put on a computerized balancer that dynamically balances the combo, this step is often ignored and is not necessary.
Well for sure it can still be balanced w/o but may end up requiring more weights added. If one takes the high/low point of both the rim and tire into consideration when mounting, it should reduce the amount balancing no?
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