Inflating tyres with nitrogen

[thirteeneast]

ORIGINAL: Mark Bennett

ORIGINAL: thirteeneast

I never top up my tyres either because the schrader is done up!.

Then you are seriously in danger of running with progressively decreasing pressures. The valves primary purpose isn't for letting the air out - it's for putting it in.
What do mean by "done up"? The only thing you do up is the dust cap - and the dust cap doesn't "do up" anything, nor help to retain the pressure in the tyre. It's just to do what it says - keep dust and debris away from the valve mechanism.

Firstly decreasing pressure would mean needing to re inflate so not sure where thats going???

Secondly a Schrader valve is removable and are hardly ever wound right in from the factory and will leak from the seal.
Nothing to do with air in or out through the valve Mark.

Have a look at a Schrader

http://patentpending.blogs.com/patent_pending_blog/images/schrader_valve.jpg

Your notice the pin winds out and if its lose will leak.

Thirdly have a look at a Schrader valve key, Its not for tightening dust caps.

 

[ralphmusic]

Alan,

I read it diligently from beginning to end and noted that the EU think nitrogen in tyres is good...

"Directive EC/94/95 of the Council dated 21 November 1994 (harmonisation of the legislation of the member states regarding the transport of hazardous goods by road) provides that use of deoxygenated air for tyre inflation is obligatory for road vehicles transporting hazardous goods, although if the vehicle is transporting the goods only within the national boundaries of the State in which it is licensed, it must comply with the provisions of local legislation"

AND

"Many manufacturers of industrial and earth moving machines recommend inflation with nitrogen as it reduces the danger of explosion due to excessive external heating, such as:
"" The vehicle catching fire;
"" Too abrupt braking;
"" Extended brake application;"

So point 1 is obviously an advantage to GT3 drivers (ho ho)


Anyway the cost is trivial and each to their own, but I still would like to understand the answers to the questions I posed in post 10 of this thread

 

[thirteeneast]

21% of Air is Nitrogen anyway I might add.[][][]

 

[chriscoates81]

ORIGINAL: thirteeneast

21% of Air is Nitrogen anyway I might add.[][][]

I thought it was closer to 70%, with 20ish% being oxygen?

 

[thirteeneast]

ORIGINAL: chriscoates81

ORIGINAL: thirteeneast

21% of Air is Nitrogen anyway I might add.[][][]

I thought it was closer to 70%, with 20ish% being oxygen?

Sorry your quite right Chris 78% according to google anyway.

So I have about 85p worth of Nitrogen in my tyres for free[]

 

[tscaptain]

In answer to your question in #10 Ralph, I believe the correct tyre pressure is one where equal temperature is achieved across the width of the tyre after hard use. Too hot in the middle and it's over inflated and vice versa if the outer thirds are hotter. Of course camber has an effect too. Reading material here..

http://www.macgracing.co.uk/trackdays_setup1.shtml

You could buy a temperature sensor - not very expensive - and play around with the pressures next time you go on a trackday[]