Volvo Owners Club Forum

Volvo Owners Club Forum (https://www.volvoforums.org.uk/index.php)
-   S80 '98-'06 / S60 '00-'09 / V70 & XC70 '00-'07 General (https://www.volvoforums.org.uk/forumdisplay.php?f=19)
-   -   V70 Wheels/Tyres: Tyre pressure? (https://www.volvoforums.org.uk/showthread.php?t=138037)

morsing Nov 6th, 2011 16:48

Tyre pressure?
 
The fuel flap sticker is slightly odd in that the pressure seems to be split in 0-100mph and over 100mph. How am I supposed to inflate the tyres whilst driving at 110mph?

Joking asside, what do they mean? Does it refer to the tyres' speed rating, that's kinda odd. Have never seen that before.

Clan Nov 6th, 2011 17:09

it means the speed you intend driving at on your trip .. however "normal" on that list is abbout 32 psi which lets the edges wear off , try 38 front and 34 rear if you dont notice any difference in ride . the new cars have ECO ratings now which are around those pressures if not higher ...

steve65 Nov 6th, 2011 19:04

as above - I run at 38 all round on 17" wheels (225/45) and it feels good

the Pirellis I just took off were on the wear bars on the edges, but 5 mm in the middle, suggesting under inflation by the previous owner

Georgeandkira Nov 6th, 2011 20:06

Hello, Tires really do slam into the pavement at highway speeds. When I take to the open road I go for the big 40 then drop it down to 36-38 front-36 rear upon arrival. The bottom line on tire pressure is that you must stay on top of it. It's a boring job which is beneath all of us I'm sure. An undetected slow leak can cost you a tire. I can't believe how often I use my pancake compressor. Kira

jadatis Nov 7th, 2011 09:51

The advice for up to 100m/h is the reference- speed for most tyre-speed codes.
Up to V the maximum load is calculated for the reference-pressure and the reference-speed of 160km/100m/h. for lower loads then maximum, the needed pressure is calculated with a formula, using this reference-maxload, R-pressure, and reference speed, and the assumed real load on the tyre.

I once got hold of this formula, and worked it out in spreadsheets.
Next link leads to my public map of skydrive, where also many English maps about tyre-pressure, even a map in wich I combine a new formula of J.C.Daws with the conventional power-formula , to one wich, to my opinion, comes closest to the ever to be constructed ideal formula.
https://skydrive.live.com/?cid=a526e...E092E6DC%21128
Download spreadsheets by clicking on the I in a circle at the end of the line, then in the right barr click download, Open in Excell or compatible program to use it. If you click wrong, the browser will try to open it, but cant handle some things I used in it.

But now your question. The advice is given nowadays for maximum load , so if you drive 110m/h with only driver and a little load, the lower load compensates the higher speed, so you can keep to the advices of up to 160km/99m/h.
Tyrepressure-advice is as you see , all about Load on the tyre, and a little bit about speed. Also the alighnment in the form of the camber angle( tyres not so |-| on the axle , but so /-\) plays a little role but mostly below 2 degrees so not needed.

If you play with my recalculating spreadsheet, the highening up for higher speed can be used too, but also you will see how low you can go for lesser load and speed.

Greatings from Holland
Peter

wowbanger2000 Nov 10th, 2011 19:03

Quote:

Originally Posted by steve65 (Post 1019874)
as above - I run at 38 all round on 17" wheels (225/45) and it feels good

Ditto. A traffic plod mate of mine says they use 38 all round.

(note - thats with Michelin XL (97 rather than standard 94) tyres).

Chris

Expolicev70 Nov 21st, 2011 08:42

I have an ex police V70 and they had preasures at 41PSI marked in door opening, I have been running it at this preasue for last 12 months on Goodyear eagle F1's and tread wear seems to be even all way across tire

Speedy Nov 21st, 2011 08:48

See now I'm on Bridgestones and I do 31/30 front and rear as per the flap and it feels great. I have inflated to a higher PSI that others use as stated on here and it feels like its on ice.

Steve.


All times are GMT +1. The time now is 08:10.

Powered by vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.