Nearly went Mad

[Baron Von Greenback]

So I had new tyres fitted and noticed it said never inflate above 40psi - I thought eh I’m around 60psi normally - on checking the tyres I noticed it said never inflate above 40psi to seat beads …. Then noticed the 65psi max inflate on the tyre - just something I saw - sounds daft but I thought I had wrong tyres on for a while - note to self look at the whole tyres -

 

[Jcloughie]

Most tyre places seem to just inflate to full pressure straight away, but I have seen the odd on that inflates a bit, then bounce the wheel a couple of times to bed it in before a final inflation. Which seems sensible to me.

Perhaps that is what is meant.

John

 

[Baron Von Greenback]

Yes it did John - just got myself in a tie as I towed to Loch Lomond last weekend and my true pal went up to 68psi I wanted to check the tyres on the side - they were filled to 60 psi as per the way of calculating the correct tyre psi - it went up by 8 psi -

 

[Jcloughie]

Yes it did John - just got myself in a tie as I towed to Loch Lomond last weekend and my true pal went up to 68psi I wanted to check the tyres on the side - they were filled to 60 psi as per the way of calculating the correct tyre psi - it went up by 8 psi -

Tyre pressure sensors will show a noticeable rise in pressure in use as the tyre warms up.

John

 

[Johnb]

We've had pressure increases of up to 9psi when towing abroad in hot weather and at speed. Interestingly the side in shade has registered a degree or two lower than the sunny side!

 

[Baron Von Greenback]

The tyre pal system recommend 20% increase from your cold to set as high alarm which for me would be 72 psi

 

[Robert_374373903]

I always pump up to 60psi but when it went into service they brought it down to 54psi. It seems the handbook said 54psi but can go to 60psi on the tyre

 

[Baron Von Greenback]

yes I set psi as per the calculation and it comes put at 58psi so will be layering some air out

 

[Baron Von Greenback]

The calc is max tyre pressure on the tyre /load index of tyre eg 65 psi/900kg x 1618 /2

so for me 65/900 x 1618/2 = 58.4psi

not what it says on tyre… this for single axle caravan btw

 

[Dustydog]

You correctly pointed out the tyre manufacturers spec. Most people haven’t a clue what goes on in the fitting bay. All tyre psi recommendations are cold. Of course tyres get hot. A hot pressure is pre calculated by the manufacturer. Never reduce pressure when the tyre is hot!

 

[Woodentop]

The max pressure embossed on the tyre sidewall is a US legal requirement and is not reflected in UK type approval.