Tyre pressure

Ganesh one more thing which has to be taken care for nitrogen (though applicable for all), always fill when the tires are cold.Do not check air after running for say more than 10 kms. The air pressure may vary on hot tires. Another point is better to get it filled from one particular shop which you feel is comfortable. Even I have noticed that different nitrogen filling stations showed different readings.

 

Cinju, yeah. The one where I have checked previously is more than 10km i am sure. I will take it tomorrow to the one nearby my house on morning. Fill exactly 32psi in that case, right?

 

30-32 is comfortable & don't mix nitrogen with normal air.

 

One advantage that I found is that the nitrogen filling stations have better equipment which are much reliable than the roadside/petrol pump ones.
I have read in internet that chance of moisture entering in inside the tire while filling is more with air. Moisture give rise to nonuniform distribution of temperature. This may be of academic interest but how serious in practical situation, I don't know.

 

Sun one more advantage which I have read is the chances of rust forming inside rims is more while using normal air as it contains more oxygen & moisture & this can be minimised by using nitrogen. Hope it makes sense.

 

Cinju, the pressure you mentioned 32/30 (front/rear) is for cold tires or a run less than 10 km. What about the level we need to stick to when there is need to refill the tires during a travel or when the tires are hot. The reason why I asked this because in fiat manual it is given that add 4.4 psi additional when the tires are hot. But if ask the shop guy to fill 36/34, he normally stares and ask why do you need that much pressure. Normally they say 32 will be fine, they don't care basically whether the tire is cold or hot. How can we properly manage the two conditions to stick to adequate pressure that the tires required when it is cold and hot. For cold tires, keeping 32/32 or 32/30 is fine from all the readings, but what about when the tires are hot. Do we really need to add 4 or 5 psi extra?

 

::O Even I am not an expert in this Ganesh. I was browsing for your answer & came across this.

Air Pressure: When and How to Set

Check and Adjust First Thing In The Morning. Set according to the vehicle manufacturer's cold tire pressure(s) recommended on the vehicle's tire placard or in its owner's manual. This must be done before rising ambient temperatures, the sun's radiant heat or even driving short distances temporarily warms the tires.

Accommodating Variables

Indoor-to-outdoor Temperature Variation. Significant differences between the conditions tire pressures are set (the warmth of an attached garage, heated garage or service shop) and in which the vehicle will be driven (winter's subfreezing temperatures) requires inflating tires 1 psi higher than recommended on the placard for every 10° F difference in temperature between interior and exterior temperatures.

Afternoon Ambient Temperature Increase.* Set 2 psi above vehicle manufacturer's cold inflation recommendations when installing new tires or if the vehicle has been parked in the shade for a few hours.

Tire Heat Generated While Being Driven (or at speeds of less than 45 mph).* - Set 4 psi above vehicle manufacturer's cold inflation recommendations.

Heat Generated While Being Driven Extensively (or at sustained speeds greater than 45 mph).* Set 6 psi above vehicle manufacturer's cold inflation recommendations.

Do Not Release Hot Tire Pressure if any of these variables could be the cause of measured tire pressure exceeding the maximum psi branded on the tire's sidewall by the 2, 4 or 6 psi indicated above for the various conditions. This temporary pressure increase is expected and designed into the tire's capabilities.

*NOTE: Tires on a parked vehicle exposed to direct sunlight will appear overinflated due to the heat absorbed from the radiant energy of the sun. Pressures cannot be accurately set on these tires until all have stabilized in the shade.

Ref:- Tire Tech Information - Air Pressure: When and How to Set.

Note:- I cannot assure authenticity of this link. But what is written does makes sense.

 

I've asked this question earlier as well but no response yet..
I'll try again.
Does tyre pressure depend on the nature (soft/hard)?

 

Nature of what?