How often?

[scotty73]

Do you check the air in your tyres?
I normally do mine once a month plus if I'm going away I'll check them then too but today while filling up i noticed my n/s/f was close to the tread marker i think that's 3mm?
Back in December it was 7mm and it's done 6000 miles the o/s/f which was about 8mm in December still looks good so I'm a tad confused

[steve_earwig]

I check mine every time I'm near an air line and I remember it (i.e. not very often with my memory )

Is the wear due to tyre pressure - is it on the outside edges or all the way across?

[scotty73]

I check mine every time I'm near an air line and I remember it (i.e. not very often with my memory )

Is the wear due to tyre pressure - is it on the outside edges or all the way across?

Very slightly more worn on the outside but i have noticed that even though i put 35psi in both fronts when i check them say 3 to 4 weeks later the drivers side is always lower than passenger today it was 31psi where the passenger was 32psi.

Ps in my original thread i said my n/s/f was the dodgy one... i cocked up.

[steve_earwig]

If it's on 1 edge that's more down to wheel alignment.

When I put my summer tyres back on in the spring I was amazed to see the pressures were still spot on. Tyre pressures do seem to change slightly throughout the year but it's probably down to the air temperature. What you have there sounds like a couple of very slow punctures.

[Welly]

Because I'm so important and special I had my tyres inflated with pure Nitrogen at one of the popular high street tyre & eggsauce emporiums about 12 months ago.

As such I no longer have the need to check my pressures, on the odd occasion that I do so out of curiosity I find them all to be reading the same

Nitrogen has large molecules which can't leak out as easily as your bog-standard 'air'

[KozmoNaut]

Bog-standard air is 78% nitrogen. You've been hoodwinked.

I check the air in my tyres once every two weeks or so. They've needed a slight bit of topping up as the weather has gotten colder, but nothing apart from that.

[rwb]

Therefore if it's only the non-nitrogen that's leaking out, then eventually all tyres must be filled almost entirely with nitrogen.

I doubt this is a commercially feasible process for isolating nitrogen.
What can you do with nitrogen anyway -- other than fill car tyres with it?

[Doggy]

Therefore if it's only the non-nitrogen that's leaking out, then eventually all tyres must be filled almost entirely with nitrogen.

I doubt this is a commercially feasible process for isolating nitrogen.
What can you do with nitrogen anyway -- other than fill car tyres with it?

...which is almost exactly how membrane separation nitrogen generators work!

[highlander]

What can you do with nitrogen anyway -- other than fill car tyres with it?

Nitrogen gas is widely used in various industries:
http://en.wikipedia.org/wiki/Nitrogen#Applications

Liquid nitrogen is also a very useful product:
http://en.wikipedia.org/wiki/Liquid_nitrogen#Uses

[steve_earwig]

Ah, after reading that it twigged - I had my summer tyres ballanced at a place in Lućko 'cos my mate's no longer have the adapter for wheels without centre caps and I remember at the time wondering why they put nitrogen in them. Now I know why

[Welly]

When I had mine filled with Nitro it was on a hot day so I went to test the tyre temps as well - all 4 tyres were running cooler than they did with 'air' in them. Nitrogen is more stable and doesn't expand/contract as much.

The high street emporium were running a campaign to 'upgrade' to Nitro to preserve tyre life i.e. they won't (shouldn't) lose pressure and start to wear out and cost you in fuel economy

[Bailes1992]

I had my tyres nitrogen filled. Didn't notice any difference at all