You can trust Bill's recommenation on this one.....NITROGEN is the hot tip
of the day.
----- Original Message -----
From: "Bill Babcock" <BillB@bnj.com>
To: "'Wes Dayton'" <oilyrag@hsrca.org.au>; "Friends of Triumph"
<fot@autox.team.net>
Sent: Monday, July 22, 2002 6:57 AM
Subject: RE: Tyre Pressure/Temperature
> Yes you can, but it's fairly hard because air is a mixed gas. Each of the
> gases has a different coefficient, so even though the pressure,
> temperature and volume are calculable with Bernoulli's formula the change
> is non-linear. You can fill your tires with Nitrogen instead of air and
> enjoy both a smaller variation in pressure with temperature and an easier
> calculation
>
> -----Original Message-----
> From: Wes Dayton [mailto:oilyrag@hsrca.org.au]
> Sent: Monday, July 22, 2002 1:40 AM
> To: Friends of Triumph
> Subject: Tyre Pressure/Temperature
>
>
> I hope my high school physics teacher isn't part of this group. Come to
> think of it, he'd likely be about 150 years old by now, so it's not
> likely!
>
> My question - is there a simple formula for calculating tyre pressure
> differentials based on the air temperature? For the moment, let's forget
> the complications involved in tyres heating up during a race (that will be
> part two of this line of questions).
>
> For now I'm just interested in the basic question "If my tyres are just
> sitting there, and the ambient temperature drops ten degrees (assuming
> that it changes slow enough so the temperature inside the tyre drops the
> same amount), how much will the tyre pressure drop"?
>
> If the formula requires me to figure out the volume inside the tyres, then
> it's probably getting all too hard. Or is it easy?
>
> Maybe I should ask this another way? Has anyone else out there spent
> Saturday getting their pre-race tyre pressures just right. Then you arrive
> at the track on Sunday morning (after a nice crisp night) and found they
> are four pounds lower and you say to yourself "do I have a leak, or are
> things as they left them or what"?
>
> Get my drift? And if I'm missing something very obvious, just be gentle
> when you let me know.
>
> And finally - yes we do spell them "tyres" and when I first arrived in
> Australia I couldn't find "tires" in the Yellow Pages until someone kindly
> pointed me in the right direction.
>
> Wes
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