GTR Forum banner
1 - 5 of 5 Posts

·
Registered
Joined
·
888 Posts
Discussion Starter · #1 ·
Well, I posted on another nitrogen/air thread that I had a all-wheel nitrogen purge & re-fill on the R35 the other day, as I was getting ready for a run.
So I got up the following morning & the GTR had a flat front tyre!
I had to pull it forward onto the drive to get a bit of room, to find the dust cap had a rubber grommet at it's base & it had slightly pressed into the valve & let the tyre down! I think the ATS guy over tightened it! This also resulted in setting off my TPMS sensor, with it informing me visit the main dealer for a TPMS ECU re-set!

So I had to fill the flat with air from my Michelin electric compressor to 32psi, to match the other 3 tyres which have nitrogen!
I'd called Litchfield & they were great & said for me to pop by & they'd re-fill with Nitrogen & clear the ECU warning for the TPMS!

On the way there, which is approx 50 miles of motorway, the 3 nitrogen tyres increased to 34psi occasionally 35psi but the normal air filled tyre that I filled shot up to 40psi occasionally 42psi!!!

So normal air is definitely less stable & subject to thermal increase in psi over nitrogen!

On a side note, I'll also be lowering my nitrogen psi to 31 so it only increases to 33/34psi when running :good:

I have to say a massive thanks to the guys up a Litchfield for their help, saying "no problems, just pop it up" :bowdown1:
 

·
Registered
Joined
·
924 Posts
Well, I posted on another nitrogen/air thread that I had a all-wheel nitrogen purge & re-fill on the R35 the other day, as I was getting ready for a run.
So I got up the following morning & the GTR had a flat front tyre!
I had to pull it forward onto the drive to get a bit of room, to find the dust cap had a rubber grommet at it's base & it had slightly pressed into the valve & let the tyre down! I think the ATS guy over tightened it! This also resulted in setting off my TPMS sensor, with it informing me visit the main dealer for a TPMS ECU re-set!

So I had to fill the flat with air from my Michelin electric compressor to 32psi, to match the other 3 tyres which have nitrogen!
I'd called Litchfield & they were great & said for me to pop by & they'd re-fill with Nitrogen & clear the ECU warning for the TPMS!

On the way there, which is approx 50 miles of motorway, the 3 nitrogen tyres increased to 34psi occasionally 35psi but the normal air filled tyre that I filled shot up to 40psi occasionally 42psi!!!

So normal air is definitely less stable & subject to thermal increase in psi over nitrogen!

On a side note, I'll also be lowering my nitrogen psi to 31 so it only increases to 33/34psi when running :good:

I have to say a massive thanks to the guys up a Litchfield for their help, saying "no problems, just pop it up" :bowdown1:
Nitrogen is no more Temperature stable than Air. Fact. Air is about 79% Nitrogen anyway.

The reason for using Nitrogen is that the molecules are bigger and do not permeate through the rubber like Oxygen so tyre pressure isn't lost.

I use plain old cheap Air and have never had any issues or differences than with Nitrogen.

I guess if you've paid for Nitrogen then you hope to see a difference but really it isn't there.

Satan
 

·
Registered
Joined
·
888 Posts
Discussion Starter · #3 ·
Nitrogen is no more Temperature stable than Air. Fact. Air is about 79% Nitrogen anyway.

The reason for using Nitrogen is that the molecules are bigger and do not permeate through the rubber like Oxygen so tyre pressure isn't lost.

I use plain old cheap Air and have never had any issues or differences than with Nitrogen.

I guess if you've paid for Nitrogen then you hope to see a difference but really it isn't there.

Satan

Thanks for your input. But I trust my on board tyre pressure readout & it said the ONLY tyre I had filled with normal air (79% nitrogen) increased massively by 10psi in pressure in just 50 miles.
Then once filled with nitrogen again by Litchfields, it matched the other 3 tyres by only increasing by 2-3psi

I'm not saying I noticed a massive difference or difference at all, as I was only on road & not pushing it on track! But having an over inflated tyre, will certainly impact not only on handling but the way the contact patch of the tyre wears. i.e.; over inflated tyres will bow out in the centre!... excessively wearing the centre of the tyre.

Oh & i'm sure that F1 teams don't give a hoot about the length of time between 'nitrogen' re-fills. It's all about stability & the contact patch of the tyre which affords GRIP, which is directly influenced by the temperature.
:popcorn:
 

·
Registered
Joined
·
924 Posts
Thanks for your input. But I trust my on board tyre pressure readout & it said the ONLY tyre I had filled with normal air (79% nitrogen) increased massively by 10psi in pressure in just 50 miles.
Then once filled with nitrogen again by Litchfields, it matched the other 3 tyres by only increasing by 2-3psi

I'm not saying I noticed a massive difference or difference at all, as I was only on road & not pushing it on track! But having an over inflated tyre, will certainly impact not only on handling but the way the contact patch of the tyre wears. i.e.; over inflated tyres will bow out in the centre!... excessively wearing the centre of the tyre.

Oh & i'm sure that F1 teams don't give a hoot about the length of time between 'nitrogen' re-fills. It's all about stability & the contact patch of the tyre which affords GRIP, which is directly influenced by the temperature.
:popcorn:
Mine are set at 30psi cold. Even in Italy on a fast twisty high speed road I only saw a 4 psi increase and the Air temp was 31 degrees.

Satan
 
1 - 5 of 5 Posts
Top