[Nikhilb2008]

The C drives will be available sometime in Jan hopefully.

[Sahil]

Ok so I got the tyres on yesterday finally after much delay from Michelin. I have driven only 20kms or so hence too early to judge. Ride quality has improved to an extent. Handling is not much different. Noise has reduced.
Overall, I frankly expected more. However it is too early to judge.

I got the tyres filled with the regular 30psi like always but somehow they look under inflated. The load index on these are same as the ones before =91. Pic attached below.

Is this something I have to live with because of soft sidewalls? If i fill more air it will make the ride harder and defeat the purpose of fitting these comfort tyres. Handling too I guess will be affected sidewall looking like this !?

[Jaggu]

The tire definitely looks underinflated?! whats the stock tire pressure for your car?

[Nikhilb2008]

The Primacy LC does have soft sidewalls. That, combined with the load of the vehicle will make it look underinflated.

Just make sure that the pressure really is 30 PSI. Check using a reliable gauge.

[Sahil]

I will get the pressure rechecked tomorrow at the pump. Typically the front wheels should have 2psi more since it's FWD ?
As in the BMW i maintain 32 at the back and 30 in the front.

My alignment seems to have gone for a toss, i have to hold the steering turned slightly to the right angle for the car to go straight.

I usually use JC auto in andheri for alignment and balancing. Any better options in bandra side? Typically what is the process to resolve the problem mentioned above? The balancing has been done and weights were added.

[Jaggu]

Originally Posted by Sahil

I will get the pressure rechecked tomorrow at the pump. Typically the front wheels should have 2psi more since it's FWD ?
As in the BMW i maintain 32 at the back and 30 in the front.

Not Really, check the door sill for the tire pressure or check the owners manual. I prefer to keep recommended pressure to save the alloys and the tires, maybe a 1-2 psi less for city drives. Always check when cold ie less than 2-3 kms of slow driving, preferably early morning or late evenings.

Originally Posted by Sahil

My alignment seems to have gone for a toss, i have to hold the steering turned slightly to the right angle for the car to go straight.

Is it with the new tire or you had the issue with the old ones also? Check alignment first. If it pulls even afterwards, then do a swap of the tires from side to side if its non directional or front to back if its directional. Should sort out in 90% of case.

[Sahil]

Originally Posted by Jaggu

Is it with the new tire or you had the issue with the old ones also? Check alignment first. If it pulls even afterwards, then do a swap of the tires from side to side if its non directional or front to back if its directional. Should sort out in 90% of case.

It started on the old tyres itself when a rod poked into the rear right tyre and damaged the sidewall in traffic speeds. Then we switched the spare wheel with that. But since then the alignment has been ruined. I wonder why since there was no damaged to the front two wheels at all.

[Jaggu]

Check alignment most logical thing to do, hope superb has no rear settings that can change?

[iTNerd]

Try 2-3 psi higher. I filled 33 psi and I find the ride/handling equally good at that pressure

[indra_slk]

Sahil I too have a Superb 2.5 V6 and also changed the tires to the Primacy LC. Did you fill nitrogen? Try filling cause it changes ride and the noise too.

[Sahil]

I checked the pressure chart in the car, its funny but it says you should maintain a higher pressure at the rear. 2.3 bar and 2.5 respectively. Which equals about 33psi front & 35 back which load of 3 passenger and luggage.since my car has 1 or 2 people in it most often with no luggage I guess 30psi all around seems fine. However I still don't get the logic of filling more air in the rear tyre when the car is FWD!

Indra, your superb is the previous generation the suspension setup would be different. I have read threads here that say nitrogen only helps maintain the pressure long and nothing else. Besides once you fill up with nitrogen you can switch back to air easily.

[Berj79]

@ sahil the tyres dont look 55 profile at all, they look under inflated, check the tyre pressure again when cold from another place, they look under inflated bigtime..

[Akki_5]

Dude, your tires are very under-inflated. If possible, inflate upto recommended pressure (33psi), try running with that for a week or so and if the ride is comfortable, stick to that. Also, check alignment by sending the car to AutoBahn (Mr. Chajju, you may use my reference; PM me for details). From my past experience, I am certain, that he will make sure your car is back to normal conditions.

[Berj79]

if the tyres are inflated to 30psi & they still look so under inflated then change the tyres asap with the tyre dealer, i guess these tyre's sidewall's cant take the superb's heavy weight with the reccomended tyre pressure.

[Jaggu]

Sahil where did you get this rule of higher pressure at front for FWD car? There is no generic rule that can be applied. It depends on the weight distribution, suspension set up and load carrying of a vehicle.

I suggest you stick to 33 Front and 35 at Rear for now (as per manufacturer recomendation), ride around for a day or two and if rear is bouncy reduce the pressure to make it 33 all around. If you still find the car bouncy reduce front by 1 or 2 but ensure sidewalls dont flex like this and the thread is wearing out proper (it will take couple of 100 kms to notice the latter).

30 for such a heavy car might be less as shown by the sidewall flex, you will land up eating the tire's faster and with a chance of sidewall and alloy damage, in my opinion not at all worth it.

EDIT: oh with such a low pressure/sidewall flex cars handling will also go for a toss, it will be really wonky