[amitverma]

since we are discussing tyres here...strange thing happened with my friend's santro,
we went to the gas station to get some more air for the rubber, i noticed that the pressure was more than the permitted air pressure reqd. how the hell is this possible...?

[MKRAFT]

When you run the car,the tires will get hot after sometime due to friction with the road surface.
thats why always check pressure when the tire is cold.
so its a good option to buy a foot pump

[Carbuff]

Yes You Are Right That There Has To Be A Balance Between The Ride Comfort And Handling While Selecting A Tyre. A Lower Profile Tyre Will Give A Better Handling But Will Reduce The Rode Comfort Due To A Short Side Wall. Thus Friends Before Selecting The Tyre See On What Kind Of Roads You Usually Drive, If Its Paved And Good You Can Go For Low Profile However If Its Not Go For A Higher Profile Tyre. But Remember To See The Rim Size And The Hib Size Of The Original And The Same Should Not Be Disturbed

[Samurai]

Originally Posted by speedsatya

the baleno comes with 165/80r13 ,circumference=1866.73mm,OD=594.5mm

so with 185/65r14,cir.=1872.7mm,OD=596.021mm

but with 185/60r14,cir.=1814.58mm,OD=577mm

Interesting. So if I consider
195/55R15, circumference=1870.82mm,OD=595.5mm Even closer. Just .22% error in speedo. Sidewall 81% of original.
195/60R14, circumference=1852.28mm,OD=589.6mm Just 2.3mm lower in height. Very little error in (-0.77%) speedo. Sidewall 88% of original.

However, moving from 165mm width to a 195mm width, would the tyre protrude out of the body? I don't prefer it. Experts please chime in.

Also what happens to the ride comfort by reducing the sidewall to 81% or 88%? I don't think there is a formula to calculate that...

[shravan316]

Aint no expert here, but, well, if you reduce the sidewall the ride will definitely be a bit more harsh at lower speeds and there is potential of the alloys breaking/cracking. Iceman's Baleno has 205 footwear, and it doesnt protrude outside. 195 shouldnt really create troubles.
Correct me if i am wrong here guys!

[Shan2nu]

Well, pratically speaking, even if you consider all the variables, finally what matters is you suspenssion setup and your tye pressure. I recently realised that my 196/60 R 14s can drastically switch between performance and ride comfort depending o it's pressure.

Iceman's Baleno running on 26 psi felt more comfy on broken surfaces, than Rudras Optra running 30-31 psi. And they both have 205/50 R15s.

So, it really isn't such a big deal. You just gotta use the right tyre pressure at the right time.

Shan2nu

[speedsatya]

Originally Posted by speedsatya

now with 155/65r13,the handling was pathetic with 5.5j rims.butwith change in rims to 5j ,things have improved .also keeping 28-31psi depending on loads.

i felt teh wider 5.5 j rim made my tire wall look smaller than the 65 profile.


[u]so i feel ,along with air pressure,the rims that u use to fit the tires is also important in deciding teh ride.[/U]

Originally Posted by Samurai

However, moving from 165mm width to a 195mm width, would the tyre protrude out of the body? I don't prefer it.

if the tires protude out,it will foul with the body when there is load inside the vehicle.also it can put excessive load on the suspension components.

also,the tires protuding out depends a lot on the rims that you use.
the same tires can handle differently oin differnt rims.as i had mentioned in an earlier post .

Originally Posted by Samurai

Also what happens to the ride comfort by reducing the sidewall to 81% or 88%? I don't think there is a formula to calculate that...

normally reducing the sidewall ,will slightly worsen your ride but improve ur handling.

but,

changing from 145/80r12 to 155/65r13 should have improved my handling as i had reduced the profile and also widen the tire.but i used to suffer from lot of understeer.also as expected the ride had deteriorated.

but when i changed from 155/65r13 to 165/60r13 potenza GIII,surprisingly my ride has improved as well as the grip levels.

so i feel that unless you really go very low profile tires ,your ride will not be that bad as compared to a higher profile.


so ,taking both ride and 185/65r14 should be the best bet on a baleno

[Shan2nu]

but when i changed from 155/65r13 to 165/60r13 potenza GIII,surprisingly my ride has improved as well as the grip levels.

Exactly, ride quality depends on a lot of things. If i were to compare the S322s with the GIIIs, i bet a 175/65 R14 GIII will give me better ride quality and handling than a 195/60 R14 S322, just bcoz the GIII is that much more superior to the S322. It's got a softer compound which improves ride and grip.

It is very possible that 2 diff tyres (model or make) with the same specifications can behave very differently.

Shan2nu

[Samurai]

Thanks guys, whatever type I pick I'll make sure it is Protenza GIII. Hey, I learnt a lot about how to pick a tyre now.

Originally Posted by speedsatya

as my 155/65r13 handles better in a 5j rim as compared to a 5.5j rim.

According to the wheel bible you showed me, the ideal rim size should be 70% of the type width. (155/25.4)*0.7 = 4.27 approximated to 4.5 inch. You deviated too far towards 5.5, switching it to 5' obviously helped. Moving to 4.5 would have been even better. Then you moved to 165 width, (165/25.4)*0.7 = 4.54 which is even closer to your 5" rim, no wonder ride improved further. Of course, I am sure GIII helped too. However, have you considered 4.5" rim?

[speedsatya]

yeah ur right.the 5.5 j rims were too wide.but i was a novice then,and accepted ahtever the tire guy gave me.
so when i put 155/65r13,still i was never happy with the handling as i have mentioned many times.

but if u see this
http://www.tongseng.com.hk/Page/Product/G3.html,
for 165/60r13,5j rims are advised for my size.
and i am more than happy with my present tires.

they are awesome.gone is the understeer and now my car feels something differnt.cannot comment on the d2,d3 eagle tires ,but these tires are simply awesome.
so have to go to the Nh17 mumbai-goa road to test it.

[Shan2nu]

so have to go to the Nh17 mumbai-goa road to test it.

LOL, i just did NH 63 and NH 17 today. GIIIs are a class apart.

Shan2nu

[zaphod]

Originally Posted by Samurai
Also what happens to the ride comfort by reducing the sidewall to 81% or 88%? I don't think there is a formula to calculate that...

The rim offset also matters in that - get something like a 32 and it will protrude - mine are 45 offset 5.5 R14's with 195/60's and no trouble, the tyres don't protrude out and neither do they foul the suspension (thanks Iceman for the advice when i got my rims and tyres)

[speedsatya]

Originally Posted by zaphod

The rim offset also matters in that - get something like a 32 and it will protrude - )

can you please explain this.????????
]how do you know what offset your present rim is.

and can the offset be changed?????

[zaphod]

I think the tyre bible link has more info on offset - basically it means how far away from the centre of the rim, the hub is mounted - for example, on a baleno, the stock is 38, moving to 32 will move the hub of the rim 6mm inside thus the rims will be more towards the outside and moving to 45 will move the hub 7mm outside and as it will be further away from the centreline the rims will be 7mm closer to the inside.

(I think a diagram would be needed to illustrate exactly how it works - check out that 'tyre bible')

too low an offset = protruding rims which may put more stress on the suspension and axles and too high may make the tyre foul with the suspension.

The rims you buy will also have an offset given in the specs - and the only way to change it is to get new rims - or you could nullify the effect of high offset by using spacers.

I hope i got that right.

zaphod

[sonic]

I've got 6" 14 inchers with 35 offset on my Baleno. No problems whatsoever with protruding tyres or fouling up the suspension.

~Sonic