nitrogen in tyres

[postie]

hi all
i have just had two new tyres put on our 1.9tdi (130) the garage put nitrogen in instead of air they told me i could mix the nitrogen with air in the tyres but only up to 15psi of nitrogen air mix which is about half the pressure for the tyres.
should i go back to garage and get them to put just air in as that seems to be all i can get from the local garages. 

[h8v]

Air is 78% nitrogen anyway, so how does that fit with the "allowable mix" theory the garage has??

h8v

[postie]

not sure but then they are tyre fitters after all
i will ask the next time i'm there.

[h8v]

I believe the theory is that nitrogen molecules are bigger than oxygen molecules and therefore pressure loss through leakage is less; nitrogen does not affect the tyre material as much as oxygen; that pure nitrogen does not contain any moisture, leading to less material corrosion.  I could go on, but try googling "nitrogen in tyres" and have a read.  It may be worth a try for aircraft tyres where safety is a priority and F1 car tyres where cost is of little consequence and the odd point one of a second really matters, but I'll stick with the 78% mix I get free from petrol station air lines.

Some people say it's just an opportunity for the tyre fitters to make a bit more money by charging you for pure nitrogen top ups from time to time, but i can't believe that could be true!!!!!!!!!

  h8v.

[danny_p]

it minamises pressure changes when the tempriture changes and it dosent diffuse out the tyer as much so pressues should be more stabel and need topping up less often. for a road car its utterly pointless tbh but that said i nitogen fill tyers but for a diffrent reason, i have nitrogen bottels on a manifold at 5bar anyway as use it for other things so i can just clip the airline on and can use the tyer inflator instantly also worked it out to be cheeper than running up the compressors

what pisses me off is some  garages charge for filling tyers with nitrogen is a rip off tho they charge more than the whole bloody bottel costs.

[Tazzy]

a mate of mine had 4 new tyres fitted to his honda s2000 and had them nitrogen filled, he said he can notice the difference in handling, he did tell me how it benefits, but ive forgotten

how much are garages charging for this?

might get it done myself...

[danny_p]

its the psuedo effect.

we have tested that one with a driver fully qualified to the higest degree as being an absolute nutter.   correctly inflated tyers with air or nitrogen handel the same when warm,  during warmup the diffrence isn't noticable because tread tempriture has bigger effect than the odd psi, you can flip the argument and say that tyers inflated with air will warm quicker