Tyre pressures

Supersonos

I have a trailer for carrying vehicles.

There's a sticker on the side explaining tyre pressures depending on payload: 1300kg - 40psi, 1500kg - 44psi, 2000kg - 60psi... and then, at 2500kg, the psi drops back down to 40psi.

Is this a typo?!  It doesn't seem to make sense that the pressure would suddenly drop back down again.  And if it's correct, why not just 40psi for everything if it works for both the lightest and heaviest payload?

AdrianC

It does sound rather bizarre. Pic?

facade

That can't be right.

The pressure should increase with load so as to keep the area of the tyre in contact with the road constant.

I'd have expected 50ish for 2000kg and 60ish for the 2500kg.

You can approximate it from the numbers on the tyres e.g. on the Suzuki max load 710kg @ 44psi, plated axle weight is 880kg, so 440kg per tyre works out to 440/710x44 = 27psi, the sticker inside the door says 29 fully laden, so not a million miles apart .

Supersonos

Here's a photo.  I got my initial weight/pressures wrong, but you get the idea.

Ganga

Is this not a standard sign for all their trailers and the higher capacity ones might have a double axle so more tyres but with less pressure.

Car_54

Supersonos said:

Here's a photo.  I got my initial weight/pressures wrong, but you get the idea.

Why not phone the number on the plate?

sweetsand

Dear OP
We had a horse trialer some years ago and the only thing I can help you with is please note the
maximum pressure your tyres can take and these are marked on the tyres.
HTH

AdrianC

Yep, I think Ganga's right.

It's not talking about the actual load, but about the gross capacity of the trailer. The larger ones will be dual axle - so 2600kg across four tyres will be the same per tyre as 1300kg across two, likewise 3000/1500.

Quick look at BJ's trailer config tool shows that 1300/1500 are indeed single axle, 2000 up are double or triple.
https://www.brianjames.co.uk/model-selector/?partner=head-office&TrailerType=open-car-transport

Supersonos

Oh.  Well that's confusing.  It's a C2 Blue which, according to their site, is 968kg capacity and 1500kg gross capacity (shouldn't that be gross weight rather than gross capacity??).  Confusing sticker, though, considering cars and vans have several tyre pressures depending on likely load - not unreasonable to assume the same with this sticker.

AdrianC

So there y'go. It's a 1500kg gross capacity trailer (968kg payload, so 532kg kerb weight), so 72psi tyre pressure.

Sure, it's going to bounce about when it's empty... It's going to do that anyway.

Herzlos

Supersonos said:

 Confusing sticker, though, considering cars and vans have several tyre pressures depending on likely load - not unreasonable to assume the same with this sticker.

It mentions gross capacity though, with most figures being in excess of what your trailer can take.

It'd be a hell of a lot less confusing and not much more work to have a different plate for each capacity - mine (not a Brian James) only has a single weight mentioned.