Switching to non-runflat tyres....

[monthefish]

Switching to non-runflats, should the pressures be adjusted?

i.e. are the standard pressures for a run-flat tyre reduced (compared to a standard tyre in the same size) due to the stiffer sidewalls?

[monthefish]

Anyone?

[B'stard Child]

monthefish said:

Anyone?

I never pay much attention to manufactures recommended pressures they are just a guide and I've found that different tyre brands need slightly different pressures

Pirelli P6000 "widowmakers" always seem to need a smidge more on my E38 (and previous Senators) than continentals or Goodyears or the sides wear faster than the centres

I just look at tyre wear on a regular basis

Is there a different pressure specified for non run flats in the handbook?

[The Wookie]

I'd actually probably recommend raising them slightly, chances are the run flat spec pressures will be low to help ride and will make a car on non runflats feel a bit lazy.

Try varying them around 0.2 bar either side of spec, you won't hurt them with that much variation.

[Vladimir]

I inflate mine to 2PSi above the recommended value for the previous (hateful) run flats.

A very good move. RFTs are cr4p.

[McSam]

The Wookie said:

I'd actually probably recommend raising them slightly, chances are the run flat spec pressures will be low to help ride and will make a car on non runflats feel a bit lazy.

Try varying them around 0.2 bar either side of spec, you won't hurt them with that much variation.

+1, the reinforced sidewall makes the tyre far stiffer, so if you go to a non-RFT you're going to need to up the pressure a little to get the same characteristics.

[monthefish]

Thanks all. That's pretty much what I thought. The ride has improved but, with the same pressures as the run flats, there's something not quite right with the handling/feel, and the fuel economy has dropped a bit.

I'll up them by a few psi and see if that improves things.