Correct tyre pressure

[Carol Anne]

Help! anyone out there with specific knowledge on tyres? I am at my wits end going from garage to garage and getting told one thing then another so I dont know what to beleive. I recently discovered that the wheels on my car are not standard for the model, but I have been putting air in them according to the handbook, which always made the rear tyres in particular, look very underinflated and pot bellied. The standard wheel for my car is 195/65R15 V with a recommended pressure of 2bar all round. However the wheels I have are 205/55R16 V. I have 2.1 bar all round at the moment but as I said the rear tyres dont look right (nothing in the boot btw). Any increase. in pressure and the ride is unbearably bumpy.
What my question is, which pressure would be technically correct for me to put in . (1998 Rover 825 2 door automatic) and am I damaging the back tyres driving with them looking pot bellied at 2.1bar?

[mr rusty]

They are lowish profile tyres so will look a bit bulgy anyway. The answer is to experiment with pressures within the range that's embossed on the tyre, to find the best ride/handling compromise: and car manufactures recommended pressures are just that: recomendations.I'd start at around 30 ish and work from there both ways.

And make sure you use your own pressure gauge: the ones on garage airlines are notoriously wrong, and your pressures may not be anywhere near what you think they are.

[Toureman]

If you start around 30psi, run your car for 200 miles then check for wear, if it is wearing in the middle of the tread your pressure is to high, wearing on the outside edges, to low.

Alternative as a good tyre fitters.

[Carol Anne]

Thanks. I was just worried that 31 might have been too low and therefore dangerous. I am going to buy a digital reader for myself!

[tom hopkins]

for the tyre sizes you mention on your car
should be 2.2 bar(31 psi) all round

[deggers316]

ask a kwikfit or other tyre company not a garage for tyre pressures or it will be in the handbook and most cars have it somewhere on the bodywork i:e: inside the door frame

[jollygreen]

A quick and easy way to check if your pressure is about right is to draw a line in chalk across the width of the tyre. Then drive tound the block for a minute or two. Have a look at the line, if it is more visible in the middle then the tyres are too flat, if it is more visible at the edges then the pressure is too high. If the line is visible consistently along its length then the pressure's fine.

Hope this helps.
JG