[ajitmoses]

Originally Posted by bala80

Which shop in chennai? Does he also stock 205/55/15 pirelli's?

Talk to Deepak @ Raja Tyres. He is a good friend. Give him my reference. 199, Pycrofts Road Royapettah, Chennai, Tamil nadu 600014, India

[nishanth.shegde]

Originally Posted by Nikhilb2008

PP2s are not available. They have been phased out more than a year back. The idea was to replace PP2s with PS3s but due to the ISI rule, that hasnt panned out the way Michelin planned.

And I dont think the PP/PP2s were budget tyres. They were always way more expensive than the other tyres. The only tyre which was more expensive was the Advan Neova.

I am planning to put 195/60/R15 on my Skoda Rapid TDI.
Any idea which brand is best for this profile. The guy from whom I am buying the alloys says Yokohama DB V580 are excellent tyres in this profile. Is that true ? Which other brands are are good ?

Thanks in advance !!

[Nikhilb2008]

DB V550 is very good. Availability is a problem. Primacy LC is the best if you ask me. Just that it's priced very high compared to the competition.

[nishanth.shegde]

Originally Posted by Nikhilb2008

DB V550 is very good. Availability is a problem. Primacy LC is the best if you ask me. Just that it's priced very high compared to the competition.

Thanks Nikhil.

Can the DB V550 take bad roads and last atleast 40K ? Also, between A-drive and DB V550 which is better considering that it will be driven mostly on quite bad roads and once in a month highway driving (again average roads).
I don't do cornering or very high speeds. My preference is good ride, less nose and a life of 40K.

[Nikhilb2008]

Originally Posted by nishanth.shegde

Thanks Nikhil.

Can the DB V550 take bad roads and last atleast 40K ? Also, between A-drive and DB V550 which is better considering that it will be driven mostly on quite bad roads and once in a month highway driving (again average roads).
I don't do cornering or very high speeds. My preference is good ride, less nose and a life of 40K.

DB V550, PLC are soft tyres. If they last more than 35k kms, consider yourself lucky. They are very soft and if you dont take care of them on bad roads, the sidewall will get damaged very easily.

Between the A drive and the V550, the V550 is a far better tyre in almost every respect. Except the A drive can survive bad roads slightly better.

[rpripr]

Originally Posted by kryptonite

With upto 2 or 3 people in the car with light luggage, the factory recommendation of 32psi (or 33psi) in front, and 29psi (or 30psi) at the rear tyres works best even for the 205/55/R15 upsize - in both city and highway driving conditions.

Still yet to try a full load of 5 people + luggage, but in any case I doubt i"ll be setting the recommended max load pressures of 36psi front, and 39psi rear, seems overkill.

Thanks for your inputs everyone!

Was trying to figure out what tyre pressure will work best. As these are cold tyre figures and if one has to drive around 3~4 kms before filling the tyres, how much should it be increased to? I currently have put it as 34 psi for both front & rear tyres. Also I have to drive over some monstrous humps everyday, should I keep the rear tyre pressure high at 34 or reduce it? My tyre profile is 195/60 R15. One problem I face is that I hear a thud sound every time I go over a speed breaker at some mild speed.

[bala80]

I use 32 psi all around in my 195/60/15, and it strikes a good balance between ride and handling. Thud/thunk sound over the speedbreaker/pothole is a charecteristic of the suspension. I thought only the vento had this issue, but looks like rapid has this too. Nothing you can do about it!

Originally Posted by rpripr

Was trying to figure out what tyre pressure will work best. My tyre profile is 195/60 R15. One problem I face is that I hear a thud sound every time I go over a speed breaker at some mild speed.

[kryptonite]

Originally Posted by rpripr

Was trying to figure out what tyre pressure will work best. As these are cold tyre figures and if one has to drive around 3~4 kms before filling the tyres, how much should it be increased to? I currently have put it as 34 psi for both front & rear tyres. Also I have to drive over some monstrous humps everyday, should I keep the rear tyre pressure high at 34 or reduce it? My tyre profile is 195/60 R15. One problem I face is that I hear a thud sound every time I go over a speed breaker at some mild speed.

What i usually do is keep my travel speed (on cold tyres) to the fuel station at a minimum and the fuel station is under 2 kms distance, then ensure the car is always in the shade through the process of fuelling which takes about 10minutes by the time they also charge my card. Then I get the air pressures checked up as normal.

Try 32-front and 29-rear as I've found the rear to be bouncy if I go higher. If not, try 32-all around as Bala suggested - one of the two will work for you. This is for a lightly loaded car (2 people with luggage).

For a fully loaded car (4 or 5 people with luggage,), tried various settings including the recommended 36-F, 39-R - but settled into using 34-all round as it gives me a very good feel.

Originally Posted by bala80

I use 32 psi all around in my 195/60/15, and it strikes a good balance between ride and handling. Thud/thunk sound over the speedbreaker/pothole is a charecteristic of the suspension. I thought only the vento had this issue, but looks like rapid has this too. Nothing you can do about it!

Yeah, the Rapid has that too, unfortunately

[Amey]

Although I am not using a Rapid but I am using a Vento TDI which we can say is pretty much the same car.
Now I replaced the tyres before I got delivery and thanks to the limited choice we have, I chose to go with S Drives because I wanted more grip and handling at the expense of ride a bit and all I can say is I am extremely happy with them.
Yes they are a bit noisy but overall pretty satisfactory. Good road holding and not too much compromise on ride quality.
Ideally would have preferred PP2 or PS3 but since they weren't available, had to settle for this.
BTW I am using 205/55/R15.

[kryptonite]

Originally Posted by Santoshbhat

Most of us believe that wider tyres have a higher contact patch and hence provide better grip or stopping ability. In reality the contact patch is a factor of the weight of the car and air pressure inside the tyre only. The contact patch area is the same with a wider or narrow tyre if the weight and tyre pressure is constant. The contact patch on a wider tyre is wider and shorter, whereas on a narrower tyre it is narrower and longer.

Wider tyers with shorter sidewalls aide cornering ability as the tyre flex is lower and results in more direct feedback to the driver.

Infact a wider tyre is more susceptible to hydroplaning than a narrower tire as it is not as effecient in disbursing water.

Wider performance tyres have better gripping compounds which generate more grip and control than standard OE tyres which our car manufactures provide. It is this quality of the tyre that improves grip and not the size per se.

Going too low on the profile increases the load on the suspension as the tyre looses its cushioning ability as there is less vertical rubber to flex, and the shock is transferred more directly to the suspension. Which is why many mfrs say that you void the suspension warranty when you upsize.

Of course one reality you cant argue with, is that cars really look hot with wide low pro tires.

Thanks for this response on one of the threads, Santosh. I tend to agree with you

So, here's an interesting theory to compliment this >> The contact patch area is the same with a wider or narrow tyre if the weight and tyre pressure is constant

In essence, if you upsize your tyre and stick to the same pressures recommended by the manufacturer, you're not really gaining anything because the contact patch remains the same. So you'll need to drop tyre pressures a little bit to increase the contact patch and take advantage of the wider tyre.

I thought there should be a logical way to compute this - by how much should the pressures be dropped or increased. And I came across this thread here:
Tire Pressure vs Tire size - RX7Club.com

The above thread's discussion is based on this principle: http://en.wikipedia.org/wiki/Gas_laws
to quote "3.If the number of gas molecules and the temperature remain constant, then the pressure is inversely proportional to the volume"

To summarize what the thread above discussed in a nutshell, assuming you've followed all the rules of upsizing by staying within 2% deviation of the stock tyre/wheel;
Now compute volume of air between the 2 tyre sizes (stock vs. upsize):

If volume of air in upsize is > than stock by x%, then drop pressure also by x% to compensate
If volume of air in upsize is < than stock by x%, then increase pressure by x% to compensate

I used this link to calculate air volume:
TRC Calculator

In my case:
Vol of 185/60 R15 is 10.1 litres
Vol of 205/55 R15 is 11.41 litres
So, 205/55 R15 holds 12.97% more air volume than 185/60 R15.

Stock pressures for 2 people + light luggage is front-32, rear-29. Going by the logic, I'll need to drop my tyre pressures by 12.97%.
Front=32psi - 12.97% = 28psi (approx)
Rear=29psi - 12.95% = 25psi (approx)

Stock pressures for 4~5 people + full luggage is front-36, rear-39. Going by the logic, I'll need to drop my tyre pressures by 12.97%.
Front=36psi - 12.97% = 31psi (approx)
Rear=39psi - 12.95% = 34psi (approx)

Not sure if this is the right way to go about it, what do you guys think?

[Santoshbhat]

Originally Posted by kryptonite

So, here's an interesting theory to compliment this >> The contact patch area is the same with a wider or narrow tyre if the weight and tyre pressure is constant

Not sure if this is the right way to go about it, what do you guys think?

Kryptonite, I did come across this theory on the net. Think of the tyre as a balloon pressing down on the floor. The contact patch should be a factor of the weight and air pressure inside the balloon. As per this theory the contact patch with a narrower tyre has more length and less width, whereas with a wider tyre this contact patch is wider but shorter (the area of contact patch being the same) . So in theory a narrower tyre will give more straight line grip while braking but will have less cornering grip, the reverse should apply for a wider tyre.

I don't think you should drop tyre pressures to achieve higher contact patch ( read grip) as drop in air pressure could be dangerous as it increases heat build up due to higher flex in the sidewall. Low pressures will adversely affect handling as well. The Grip is as much a factor of tyre compound as it of tyre width.

[kryptonite]

Originally Posted by Santoshbhat

Kryptonite, I did come across this theory on the net. Think of the tyre as a balloon pressing down on the floor. The contact patch should be a factor of the weight and air pressure inside the balloon. As per this theory the contact patch with a narrower tyre has more length and less width, whereas with a wider tyre this contact patch is wider but shorter (the area of contact patch being the same) . So in theory a narrower tyre will give more straight line grip while braking but will have less cornering grip, the reverse should apply for a wider tyre.

I don't think you should drop tyre pressures to achieve higher contact patch ( read grip) as drop in air pressure could be dangerous as it increases heat build up due to higher flex in the sidewall. Low pressures will adversely affect handling as well. The Grip is as much a factor of tyre compound as it of tyre width.

Thanks for the response!

But I had to try out the theory I outlined earlier (for myself of course ), then I realized 28-F, 25-R was probably too less to cope with our Bangalore road conditions. So, I gave 30-F, 27-R a shot for the last 3 days. At these tyre pressures, I must admit, the steering felt a little stiffer, and in fact also seemed to give me more feedback from the tyres! At slow speeds, the ride was oh...so...soft as well. But going over small bumps & uneven roads at moderate-to-high speeds wasn't at all comfortable and felt as if the suspension crashed & clunked even harder than normal through these bumps/potholes.

So, back to 32-F, 29-R for upto 2 people + luggage;
and 34 all-round for 4~5 people + luggage for me!

Cheers!

[Chik18]

Hi All,

Just booked myself a Skoda Rapid TDI Ambition... Wanted more information on whether i could shod them any of the following options:
> 215 rubbers of any kinds
or
> 16" alloys

Thanks,
Mahaan

[DieselDon]

Originally Posted by Chik18

Hi All,

Just booked myself a Skoda Rapid TDI Ambition... Wanted more information on whether i could shod them any of the following options:
> 215 rubbers of any kinds
or
> 16" alloys

Thanks,
Mahaan

Hi Mahaan

Do let us know what option you went ahead with.

Best Regards, D

[Surprise]

Originally Posted by nitrous

195/60/15 if you want ride and handling.
205/55/15 would make the car handle, but you'll lose a lot of the ride quality.

PCD of rapid? Just wanted to check out is 195/55/R15 a right upgrade for Rapid?