Nuclear Nick wrote: ↑Wed Aug 22, 2018 7:03 am
No, you won't feel 1 psi difference, and it won't make any difference to handling or tyre wear, hence my question about the reason for doing it. But if it helps psychologically there's no harm in it.
Yep 1 psi is merely in the "noise" given all the other factors affecting handling and wear.
But it is good practice to use an accurate tyre gauge and check tyre pressures regularly when cold, as they can change quite considerably with the weather and leaky rims. TPMS is really only for detecting punctures, although they should be accurate within 1 psi anyway. It's just that TPMS is not very convenient when setting pressures as the readings shown are not instantaneous. The way I use TPMS is to set the cold pressures with a gauge and then take note of the TPMS readings (which are usually within 1 psi). Then use the TPMS display to keep an eye on them. If I see that the TPMS readings have changed more than 1 psi from cold, I know to check and adjust for the weather or any slow loss of pressure over time.
I never use garage tyre compressors either. They usually have crap gauges and are a pain to use. So I normally use a bike track pump for top ups at home. Usually only putting in 1 or 2 psi anyway.
Nuclear Nick wrote: ↑Wed Aug 22, 2018 7:03 am
No, you won't feel 1 psi difference, and it won't make any difference to handling or tyre wear, hence my question about the reason for doing it. But if it helps psychologically there's no harm in it.
Yep 1 psi is merely in the "noise" given all the other factors affecting handling and wear.
But it is good practice to use an accurate tyre gauge and check tyre pressures regularly when cold, as they can change quite considerably with the weather and leaky rims. TPMS is really only for detecting punctures, although they should be accurate within 1 psi anyway. It's just that TPMS is not very convenient when setting pressures as the readings shown are not instantaneous. The way I use TPMS is to set the cold pressures with a gauge and then take note of the TPMS readings (which are usually within 1 psi). Then use the TPMS display to keep an eye on them. If I see that the TPMS readings have changed more than 1 psi from cold, I know to check and adjust for the weather or any slow loss of pressure over time.
I never use garage tyre compressors either. They usually have crap gauges and are a pain to use. So I normally use a bike track pump for top ups at home. Usually only putting in 1 or 2 psi anyway.
If you are really concerned with accuracy of your tyre pressures, then get your OPC or tyre fitter to fill with Nitrogen. If they do it properly they will purge all the air from the tyres and with the nitrogen in the pressures will stay very much constant as it is the moisture when filled with air that causes the variations.
Third stage wrote: ↑Wed Aug 22, 2018 1:34 pm
If you are really concerned with accuracy of your tyre pressures, then get your OPC or tyre fitter to fill with Nitrogen. If they do it properly they will purge all the air from the tyres and with the nitrogen in the pressures will stay very much constant as it is the moisture when filled with air that causes the variations.
Yes, nitrogen is a little better, but really not necessary unless you are competing on track professionally. In F1 we experimented with all sorts of gases and found very little advantage over a standard air compressor. Nitrogen in road car tyres is more of a marketing gimmick than a real world benefit, but doesn't do any harm unless you are paying for it!
On a car used for daily driving, none of this stuff matters a toss as long as your pressures are not way off the mark. The manufacturer recommended pressures are very much on the safe side and you could go a fair bit lower for ultimate grip and ride comfort, but at the risk of uneven wear and rim/sidewall damage etc. Basically it's best to stick with the manufacturer recommendations to be safe, but I often used to run my 911 (997.2) rear pressures a fair bit lower as the recommended pressures were insanely high. Even the local OPC used to set them lower.
Someone in a previous post discussing Nitrogen filled tyres also said the Nitrogen molecules were smaller and therefore more likely to “escape” than the bigger N and O2 mix....(!)
