A few months ago I had new tyres fitted and got tempted into having them filled with nitrogen.

There was a debate as to whether it was practical or just a bit of a waste of time.

The time has come to share a couple of observations I have made.

1. Since having nitrogen put in I have checked tyre pressures weekly (as any diligent driver would do) and have seen no variation in pressure when measured cold.

2. I also checked pressures a few times when warmed up after medium/long distance runs (over 50 miles but less than 200 miles).

I have noted pressure increases at less than 1-2 psi in these situations.

My findings lead me to the conclusion that nitrogen filled tyres are more stable, less likely to lose pressure (and definitely not to the level where dangerously low pressures could cause excessive wear or handling problems) and allow me to save time having to top the tyres up weekly.

Thats very interesting -

There was a thread a while back and many on the forum believed it was a gimmick and not worth bothering with

It has been used quite a long time in racing and there are definate advantages, but there are some disadvantages as well

For example,

1 - if yiou had a slow puncture, you would have to top it up with nitrogen (which may be inconvenint)

2 - Some FOC members live in remote locations, a long way from a source of nitrogen

3 - You have to do all your tyres, there may be a charge for that (especially if you did not buy your tyres from the place that supplies the nitrogen)

4 - Many cars have 2 sets of recommended pressures - one (lower) for normal driving and another (higher) for high speed / heavily laden - adjusting them could be inconvenient if you have to go to your tyre fitter every time

5 - If you have spent hours, weeks months or years experimenting with/ adjustion tyre pressures to get them spot-on (balancing wear, ride, handling and economy) on your souped-up Mondeo you wouldent want to have to start again from scratch

A theory -

Because the pressures rise less when warmed up, you shoud start with higher pressures from cold with nitrogen eg-

Normal air say 36 cold and say it rises 4 psi = 40 hot -

Nitrogen if its 36 cold its only going to reach 38 hot, less than air, so it needs to start at 38 cold to reach as much as normal air when hot (40psi) - assuming the normal air rises 4psi and the nitrogen 2psi

My front tyres get very hot and i can't remember how much but i think the pressures rise rather a lot - nitrogen may be a good idea for me too and i am considering using it when i get my new alloys