Need more info.
Total weight or max permissable vehicle weight.
From tyres: maxload or loadindex, kind of tyre to determine the referencepressure, and last ( but not superimportant, speedcode.
Collect those data, and I will put it in my made calculator.
The kind of tyre:
1. Standard load personscar , referencepressure 2.5bar/36psi
2. Extraload personscartyre AT 2,9bar/42psi
3 . C-LOAD / 6PR C or LT tyre AT 55psi/3.75 bar.
4. D-LOAD / 8PR C tyre AT 4.5bar/65psi.
In European system there are exeptions in the referencepressure, american not.
So if you see something like this " maxload 500kg AT 50psi, that is the reference-pressure.
On personscar only the maximum allowed cold pressure is given, from 44 to 51 psi, and XL sometimes even 60 psi., but the referencepressure is lower. On C tyres only referencepressure given.
As well is two words!
How does a sage know everything about everything? or does he? or does he just think he does?
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Quote: Originally posted by blueexpo97 on 28/12/2021
32-36 psi according to a previous post.
surely those pressures are for car tyres and not the commercial/van tyres normally used on trailers
OP needs to give the full info taken from the side wall of the tyre or better still a picture of the info
My caravan is on van tyres and the recommended pressure according to my handbook is 36psi, so I would think that 32-36 is almost certainly right. Newer, heavier caravans on larger wheels have higher pressures from what I have seen.
Quote: Originally posted by marg6 on 28/12/2021
ok so what is the full size for yours Colin?
I presume you mean the tyres, and they are 175/80/x 13, commercial rated tyres, as specified in the handbook, and the recommended pressures are 36psi. That is what I always run them at and they have always been fine. I had a new set put on last year. The caravan has a maximum gross weight of 954kg. Even the largest model in that range only runs at 51psi and that is quite a bit bigger than mine.
Topicstarter Romperstomper, did not react, I think he got no messages of new posts, I did not either, checked my mailadres, was the right one.
But OK , Collin gives 954kg ( conversion of 2100lbs) And 175(80)R 13 , and that I googled and used in my made calculator, wich gives higher advice then yust MPVW with no reserve, as most caravan makers use for their advice.
Found 3, and used 1000kg because lighter caravans often overloaded.
1. Normal car tyre LI 86/ 530kg AT
36psi/2.5bar , advice 37psi / 2.6 bar.
2. XL / reinforced/extraload LI89/ 580kg AT 42psi/2.9bar, advice 39psi/2.7bar.
3. 8 PR/D-load C(omercial) tyre LI 97/730kg AT 65psi/4.5bar, advice 47psi/3.2bar.
This all with maximum reserve, with still no screws trembling loose, or doors open after the ride.
A stiffer tyre ( 8pr LI97 stiffer then personscartyre LI86) needs higher pressure for the same weight on it, because at same deflection lesser surface on the ground.
And the 86Li has only poor reserve for the weight, for that reason needs higher pressure then the reference of 36 psi. Allowed for personscartyres upto max cold pressure writtten on sidewall of 44 to 51 psi.
On C-tyres only referencepressure is given on sidewall, and nowadays not allowed higher, in earlyer days it was allowed and even used up to 40% higher.
Continental groop often gives " max inflation pressure " of 10psi higher besides the referencepressure on sidewal, and then its allowed. Both are cold pressure, so when temperature of gascompound in tyre is the same as outside tyre air. That is when not driven long enaugh and no external factors like fi sunshine on tyre.
hi thanks for all your input,s van in garage at the moment so cant give tyre size but colin is about right 33 to 36 psi,tat s what i was told by a van dealer .
Quote: Originally posted by romperstomper on 30/12/2021
hi thanks for all your input,s van in garage at the moment so cant give tyre size but colin is about right 33 to 36 psi,tat s what i was told by a van dealer .
Yep, really really sorry romperstomper!
I was the first to answer with 32-36psi and apologies again, I was a pound out!
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Topic: tyre pressure
via mobile 28/12/2021 at 11:51am
