mark61
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No.
No.
Don't know.
No idea.
Never even been stopped even when my tyre pressures have been very low, but then I don't hammer down a motorway when my tyres are at 1bar.
Tyre pressures
- Thread starter Herman
- Start date
No.
No.
Don't know.
No idea.
Never even been stopped even when my tyre pressures have been very low, but then I don't hammer down a motorway when my tyres are at 1bar.
molly 2
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My van has camper tyres fitted from new plateed at 5,0 bar front ,5 5 rear ,that is higher than a fully .loaded boxer van
Millie Master
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Yes, I have seen the DVSA doing road side checks at their testing station alongside the A52 to the East of Grantham as well as at a similar location to the West of Sleaford alongside the A17 and I have read on several Facebook motorhoming groups as well as another forum of similar road side tests, so it might be better not trying to be a smart ass!
Tookey
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It's a peice of paper, why would you not. You carry a warning triangle, a spare tyre, fire extinguisher etc with the hope you never use them so I don't see why this is any different.
It takes up no space, adds no weight and might prevent a load of hassle (especially if abroad), no brainer as far as I'm concerned and will follow the advice when I get new tyres.
in h
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The difference is that the warning triangle and fire extinguisher are legal requirements in some places. The spare tyre is of use to me.
in h
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I have seen DVSA doing vehicle checks. That's not to say that they were checking tyre pressures.
Because I have read it on Facebook does not make it a reality.
Tookey
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Fair points
Canalsman
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Those pressures sound way too high in my view.
The camper tyres will have been fitted by the converter in place of the van tyres fitted when the base vehicle left the factory.
in h
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It's easy for anyone to establish the correct tyre pressures for themselves, by loading up FULLY and going to a weighbridge (complete with passengers and pet dog/gerbil/hippo).
From the individual axle weights, it is easy to calculate the correct pressures.
Without that information, it is impossible; so the maker and the converter and the tyre company understandably play safe and suggest the highest possible pressure, with a bit extra added for a safety margin. And everything rattles, the handling is terrible and the tyres wear in the middle.
From the individual axle weights, it is easy to calculate the correct pressures.
Without that information, it is impossible; so the maker and the converter and the tyre company understandably play safe and suggest the highest possible pressure, with a bit extra added for a safety margin. And everything rattles, the handling is terrible and the tyres wear in the middle.
in h
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Indeed, it is worth slightly less than the paper it is written on.
If you like, I can send you an email from God, or from the tyre manufacturer of your choice, that says your tyres should all be at exactly 17.25psi.
And if you were to be stopped by VOSA and had your vehicle checked over, how much notice do you think a trained vehicle examiner would take of a bit of paper? They know that the correct pressure depends on the load, not on a bit of paper, or, indeed, on a plate screwed to the vehicle.
in h
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I've no idea what the 4/6 psi rule is, but for four and sixpence, you could probably buy one shot at a garage tyre pump.
I puffed my car tyres up yesterday morning, before it went for its MOT at lunchtime.
The TPMS told me that the tyres were at 31psi all round.
I had to do a trip out today, doing about 70 miles, mostly on motorway. It has been a hot day.
The temperatures rose to 34, 34, 35 and 37 degrees, the pressures rose to 33, 33, 35 and 36 psi
Make what you will of that: I don't usually take that much notice, but I wanted to know if one has a leak.
in h
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My tyre pump seems to use normal air, so they are 78% nitrogen-filled.
Pressure variations with temperature are not a problem as far as I can see.
Tookey
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ok, I get the maths bit, where I am still a bit lost is how it takes into account the actual tyre and the variables that come into play with different makes/models
molly 2
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In my view and the view of the motorhome manufacture that is the correct pressure
mark61
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Well, I guess if you average out your rise in psi, your roughly at 4 psi, good enough to prove the rule
The 4/6 psi rule has been around for years. Some people even go so far as say that's how manufacturers work out psi for loads.
Strangely, although theres a lot of stuff about the rule online, Coopers appear to be the only manufacturer to mention it, or the only one I've seen.
I've never taken too much notice of the rule, apart from notice that on good tarmac it seems to be pretty close to what TPMS show. The rougher the roads, the more "out the window it goes"
No where near as accurate as working out psi by going to weigh bridge and working from load rating, but probably more accurate than pumping up to full psi because thats what the plate say.
mark61
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Because the load rating of the tyre is part of the calculation.
mark61
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They have no idea if your van is empty or fully loaded.
in h
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Yes, but in the view of someone who had the facts at their disposal, you would get a very different number.