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[Dennis C]

It is quite difficult to visualize a mole of something because Avogadro's constant is extremely large. For instance, consider the size of one single grain of wheat. If all the people who have existed in Earth's history did nothing but count individual wheat grains for their entire lives, the total number of wheat grains counted would still be much less than Avogadro's constant; the number of wheat grains produced throughout history does not even approach Avogadro's Number.

Confused of Yorkshire. It was only a puncture you see discussing?, 🤔🤔🤔

[Leon Novello]

Checked the tyres on the Mazda 626 this morning after filling up. The service station digital gauge read 32psi, my pencil gauge read 38psi. I`ll go into a different garage with a digital gauge to double check. I don`t use nitrogen, at my speeds, it`s a waste of time and money.

[Beezabryan]

Reading Avogadro's Law had me wondering if I should or should not check, recheck and possibly adjust my tyre pressures taking into account the ambient temperature here and that of my destination not forgetting the load to be carried before or after taking a dump or maybe a leak.
Oh sod it I'll just go for a ride

[papasmurf]

I check tyre pressures before using any of our motorcycles. I add a couple of PSI if fast long distance travel is involved. I also adjust the pressures when extra loads are carried.
I have also made an adaptor so I can connect a small 12volt air pump to the Optimate charger plugs fitted to the our motorcycles for when we go to rallies so I can check the pressures before we return.

[jefrs]

rofl - Avogadro's number is a googleplex i.e. too big to understand. What is useful is the 'mole' unit which although this is the weight of an Avogadro's number of molecules, it is also the molecular weight of the element in grams i.e. Oxygen atomic mass 16, molecular weight (as O2) 32, mole of oxygen 32g. This serves two purposes, it tells us how much stuff we have - we can weigh it, and its molecular density because a mole of gas occupies 22.4 litres. The atomic mass/molecular weight is also directly related to molecule size. The science behind this stuff, and the gas laws, allows us to do things like calibrate your tyre pressure gauge. Which is needed because as you may have noticed the ones by the petrol pumps are wildly inaccurate.

[PeteF]

I think, for all practical purposes, you can ignore the gas permeability of inner tubes and tyres.
As for using nitrogen; on an Enfield?

[Caboose]

Puncher!
When I saw the heading I was expecting a tribute to Cassius Clay or possibly Henry Cooper, but no, it seems it's all about a PUNCTURE in a motorcycle tyre!
Regards Dick.

[jefrs]

Assuming you don't lose air, you can calculate the change in pressure and temperature by the Gay-Lussac equation P1/T1 = P2/T2. I.E. T2=P2T1/P1. Back of envelope - an increase during riding from 30psi to 35psi indicates temperature in the tyre raised from 20°C to 69°C. Typically during a run we see only a very small rise in pressure whilst the tyres can feel warm to touch.

[jefrs]

If you leave a bike untouched over winter in the shed, the tyres go flat. This is not Murphy's Law but due to permeability of the tube. The gas escapes through its wall, it is not a puncture, it's why balloons deflate. I imagine you check the pressures before riding then and hence are not ignoring permeability

[Exile]

Wow. Or is that woe...? This is what the guy asked..: "The question. Is the tyre TUBELESS because that what it says on the tyre, or does it have an inner tube?"



It has an inner tube. It's broken. Replace it with a new inner tube and then pump it up with whatever atmospheric gas you have available.

I would suggest air.

Good luck with it Foz...