Tyre pressures

[Hutch]

I have just been on the Coachman owners website on Facebook.
Somebody asked about the correct tyre pressure for their caravan. Almost 50 % of the replies answered that the pressure was on the side wall of the tyre. I tried to point out that was the maximum pressure allowed for the tyre when cold.
How many people are running around with tyres over pressurised,

Edit. For the weight of their caravan.

 

[RogerL]

I have just been on the Coachman owners website on Facebook.
Somebody asked about the correct tyre pressure for their caravan. Almost 50 % of the replies answered that the pressure was on the side wall of the tyre. I tried to point out that was the maximum pressure allowed for the tyre when cold.
How many people are running around with tyres dangerously over pressurised.

Most single axle caravans have tyres specified only marginally above the caravan's MTPLM so have to run at maximum tyre pressure - unlike cars which get tyres rated at 30-40% above the maximum axle loading AND are speed rated way above the legal limit.

So I doubt that many caravan tyes are "dangerously" over-pressured.

 

[Woodentop]

The max pressure embossed on the sidewall is to meet US market requirements and has nothing to do with the UK.

 

[RogerL]

The max pressure embossed on the sidewall is to meet US market requirements and has nothing to do with the UK.

They aren't mandatory in UK or EU law - but the maximum cold pressures shown are still the maximum cold pressure the tyre should be used at.

 

[JTQ]

The max pressure embossed on the sidewall is to meet US market requirements and has nothing to do with the UK.

However, the ability of the tyre does not change by crossing the pond, allowing us to inflate to higher values.

What might not be clear, it is a maximum inflation pressure with the tyre at ambient temperature, not its maximum running pressure in use. Running it will exceed this pressure by quite a bit as we here typically are running SA van tyres at or near their maximum loading .

 

[otherclive]

I have just been on the Coachman owners website on Facebook.
Somebody asked about the correct tyre pressure for their caravan. Almost 50 % of the replies answered that the pressure was on the side wall of the tyre. I tried to point out that was the maximum pressure allowed for the tyre when cold.
How many people are running around with tyres dangerously over pressurised.

Hopefully they don’t do the same with any of their cars’ tyre pressures.

 

[Hutch]

Most single axle caravans have tyres specified only marginally above the caravan's MTPLM so have to run at maximum tyre pressure - unlike cars which get tyres rated at 30-40% above the maximum axle loading AND are speed rated way above the legal limit.

So I doubt that many caravan tyes are "dangerously" over-pressured.

I have given an edit to my OP to.
Over pressurised for the weight of their caravan.

 

[GUMPY]

Just looked at my van tyres they are rated 850kg at 65psi cold single tyre.
1500kg van, sticker says 59psi however I run at 60psi cold as depending on the manufacturers literature you read the TP can be 59 or 60 for the same tyres on the same model van depending on the mtplm 🤔
As for running they can hit 70psi on a long run but tend to sit about 67-69psi.

 

[JTQ]

As for running they can hit 70psi on a long run but tend to sit about 67-69psi.

In my experience not at all unusual with SA caravans, the tyres really do get up to pressures that are surprisingly high, well 'surprising' till you know they will.
Plus, it can be observed which side the sun is shining on the long hauls where one side runs in sunlight the other in shade. Additionally, a down pour has a marked effect lowering from the hot running value.

Sometimes I think the monitoring system gives more info than I need. Critical to me is if the pressure goes lower than the static inflating value, then I know there has to be an issue I need to react to. Much else is rather academic, and I have to trust the tyre designer has accounted for all these things as constructively evaluating them myself is beyond my knowledge base.

 

[GUMPY]

In my experience not at all unusual with SA caravans, the tyres really do get up to pressures that are surprisingly high, well 'surprising' till you know they will.
Plus, it can be observed which side the sun is shining on the long hauls where one side runs in sunlight the other in shade. Additionally, a down pour has a marked effect lowering from the hot running value.

Sometimes I think the monitoring system gives more info than I need

Yes I agree but I just love watching data😎

 

[JTQ]

Yes I agree but I just love watching data😎

So do I, its a drummed in engineering thing, just with having to drive I can't also log it in my note book! Not dared asked the co pitot.

 

[Sam Vimes]

Just an aside on TPMS systems. I have this on my car but one tyre sensor got destroyed when a stone went through the tyre. The replacement always reads 1PSI lower than the others. It really irritates me but I can't do anything about it.