Nitrogen tyre fill, hidden charges.

=rizla=

I remember watching a show about a new GT racing team (I think Noel Edmonds was involved, 12 months from planning to racing at Le Mans 24hr), they had a problem, take the car out, a few laps later lap times were down, driver complaining etc, turns out the tyre guy was filling the tyres up via a normal airline and not nitrogen. I seem to remember it was to do with the water vapour in air, although could be wrong.


Either way it definitely changed the pressures on a RACE car after a few 'hot' laps, and therefore the handling, I seriously doubt anybody driving a normal road car normally will benefit at all from nitrogen in their tyres.

facade

The heavier than air gas you can use to sound deeper is Sulphur Hexafluoride.
You do have to hang upside down to get it out of your lungs though, before you suffocate.

I think nitrogen fill is a waste of money too.

photome

I noticed a nitrogen fill charge that I hadnt asked for from Kwik fit last time I had new tyres , I wasnt paying so didnt say anything, but its a bit crafty

Joe_Horner

Aretnap wrote: »

Pedantically that's only strictly true of ideal gases, of which there are none. Practically of course oxygen and nitrogen do behave pretty much like ideal gases at normal-ish temperatures and pressures, so any differences in the pressure change as they heat up will be negligible for most purposes.

Yeah, I was struggling with my inner pedant as I typed it but figured the difference in a car tyre is so minimal that it wasn't worth confusing the issue

Joe_Horner

=rizla= wrote: »

I remember watching a show about a new GT racing team (I think Noel Edmonds was involved, 12 months from planning to racing at Le Mans 24hr), they had a problem, take the car out, a few laps later lap times were down, driver complaining etc, turns out the tyre guy was filling the tyres up via a normal airline and not nitrogen. I seem to remember it was to do with the water vapour in air, although could be wrong.

Moisture in the air will do it. In a cool tyre it'll tend to condense, then turn back to vapour as it heats up. That gives a big pressure change as you're effectively adding more gas to the tyre.

lighting_up_the_chalice

I would say, in a regular tyre, on a regular car, that altitude would be more likely to have an effect on pressure than air/nitrogen.

kirkofski

Surely, unless they fit the tyre to the rim in a nitrogen filled room, there's still going to be a percentage of oxygen in the tyre anyway?

I had the same issue with a local garage when I went in for a puncture repair. I was quoted one price over the phone but then they wanted to charge me extra after they had done the work for filling with nitrogen. I played them a recording of the phone call and they reduced the bill.

patman99

Nitrogen has bigger molecules than oxygen, so is less prone to leakage.
Well, thats the theory anyway. I had my tyres done by a local garage after winning a free re-gas via fb.
Failed to notice any difference.

Joe_Horner

patman99 wrote: »

Nitrogen has bigger molecules than oxygen, so is less prone to leakage.
Well, thats the theory anyway. I had my tyres done by a local garage after winning a free re-gas via fb.
Failed to notice any difference.

That's fine as a theory except that, by the time you've topped up about 4 times for "oxygen leakage" you're up to something like 99.98% nitrogen in them anyway because each top-up replaces the "lost oxygen" with another 79% or so of nitrogen

Richard53

The OP doesn't say how much the charge was, or whether it was paid.

Personally, there's not a chance in hell I would pay this. Not asked for, not wanted, therefore not paid for.