The right tyre pressure?

[BikerSG]

Hi All,

I have upgraded my Sonata's tyres from 195/65/15's to 205/65/15's. They have solved the problem of the Sonata being too low, just as I had hoped.

But the tyres seem to be wearing off too fast. I am running 33psi pressure (oe is supposed to be 32). If the tyres are wearing out oo fast, it usually means that the tyre pressure is too low.

So my question is how do u know what tyre pressures to keep to achieve optimum grip and wear & tear?

I had read up on some forum a suggestion to draw a straight line on any of the tyres accross the width, using white chalk. And then to drive around for about 10-15kms at normal city driving speeds. If the chalk had worn out evenly from all over the tyre, then the tyre pressure is correct. If the tyre pressure had worn out more from the centre, then the tyre pressure was more.

Has anybody tried this? Or any other method to arrive at the right tyre pressure?

[Rehaan]

Originally Posted by BikerSG

But the tyres seem to be wearing off too fast. I am running 33psi pressure (oe is supposed to be 32). If the tyres are wearing out oo fast, it usually means that the tyre pressure is too low.

Hey BikerSG,

Not neccesserily true. As you yourself said, low pressure causes more wear on the sides of the tires and not in the center.

Two Qs -
1. How many km have you driven with these tires?
2. What makes you think they are wearing fast?

I think that 33psi is fine, and i doubt the tires are really wearing as fast as it appears.
However, do keep in mind that if the tires are getting worn on just one side the chances are its an alignment/camber thing.

cya
R

[BikerSG]

low pressure will not cause more wear on the tyres. if the pressure in the tyres is low, the tyre will be deflated the same amount everywhere.

but it doesnt work like that for overinflated tyres. If the tyre is overinflated, it will start to balloon out and the centre of the tyre will start to wear out more than the sides.

I have run the 205/65/15's for less than 5,000k's now. There seems to be at least 30% difference between existing front tyres and 1 new tyre which I bought to replace a damaged tyre.

Keep in mind that the car is chauffeur driven 95% of the time - that means slow and smooth! With this style of driving the tyres should last more than the projected 15,000 k's that I am expecting with 33psi!

I intend to try the chalk system sometime this week as soon as I have some time! I wanted to know if somebody on tbhp knew of another way!

[manaa45]

if the tyres are wearing faster from the one side the probable problem must be the balancing or something to do with the camber. get the balancing of the car checked and have rotation of the tyres done once in 8/9 months so that the wear is not only from one side.

33 psi seems to be ok and when u have a driver who drives so well teach him a thing or two abt the repairs of hte vehicle too.

[BikerSG]

in my second post, (post no. 3) the first sentence is wrong. I meant to say - low pressure will not cause more wear on the sides of the tyres.

all my cars are regularly balanced and aligned! the guy also makes it a point to rotate the tyres!

So i dont think misbalanced or misaligned wheels are the result of the excessive wear. I had previously put 17's on my sonata with 245/40 tyres on it. I was runnning 42psi pressure. Changed them cus my suspension had started to show signs of aging. I guess the sonata's suspension wasn;t designed to work so hard

[speedsatya]

Originally Posted by BikerSG

I have run the 205/65/15's for less than 5,000k's now. There seems to be at least 30% difference between existing front tyres and 1 new tyre which I bought to replace a damaged tyre.

hey biker,
is ur tire of a softer compound not meant for our roads????
as in 5000kms ur tire has worn 30% that means in abt 16000kms ur tires will be worn out completely.
tats ridiculous.
if its uneven then u can understand its a balancing or alignment problem.
maybe u can use a trial n error method.as 33 is causing problems ,u cud try increasing by 1-2 psi and find the ideal pressure.
as ur present OD is more ,maybe u require more air inside

[BikerSG]

OD has increased with the entire increase coming from the tyres alone. Thats why I increased it from 32 (OE) to 33.

Tyres are Goodyear eagle F1's.

I am going to try out the chalk method this sunday!

[nitrous]

hey bikersg,

there might be problems with either ur alignment or suspension. i live in chennai too. maybe we can work on the problem. pm me asap.

btw, where do u get ur wheel alignment done?

[BikerSG]

alignment and balancing is done by bm lal on lloyds road

[Shan2nu]

They say that incresing or decreasing the Overall Diamater of the tyres can affect the suspenssion setup. This could be one of the reason's.

Which part of the tyre is wearing off? inner side or outer side? And on which tyre/s.

Shan2nu

[BikerSG]

the tyres seem to be wearin g off quite evenly. Its just that they are wearing off faster than normal.

tyres are goodyear eagle F1's.

[Rehaan]

Originally Posted by BikerSG

the tyres seem to be wearin g off quite evenly. Its just that they are wearing off faster than normal.

In that case, the chalk trick isnt going to help much, (unless there is some uneven wear happening).

Sometimes just the dust and dirt on the tyres make them look worn.
Why dont you measure tread depth on the older tyres and on the new tire and see the difference in measurement. Then calculate using that rate, how long the tyres will last.

cya
R

[Shan2nu]

If they're wearing out evenly. Then there can't be anything wrong with it.

Maybe the tyre compound is soft, that's why it's wearing off. Anush's Michellin tyres on his Vtec too seem to be wearing off pretty quickly. maybe that's how the tyres are meant to be. You can't have tyres that grip like crazy and not expect them to wear off.

Bridgestones on the other hand, last a life time. The S322s' on my Vtec have been driven hard for 46K now and there still seems to be enuf tread left for a few more 1000 kms.

Another Honda City in Hubli has done 60K+ but it's tyres have deeper tread than on my car, ofcourse that car has never been ripped. He drives it normally, with minimal wear and tear on the tyres.

Just wondering, does vehicle weight add to tyre wear?? Technically it should, to a certain extent.

Shan2nu

[DCEite]

Can someone please tell me what would be the ideal tyre pressure for the following cars:
1. Maruti 800 (dont know tyre profile)

2. Maruti WagonR/Santro Xing : 145/70-R-13

thanks in advance..

[speedsatya]

wagon r

155/65r13 is 32psi
145/70r13 is 33psi

santro
155/70r13 is 28 psi

M800
145/70 r12