About Tyre Pressures

[Malko83]

Hello IQ fans

Hello David

A little help about tires pressure please

It is written inside the door 2.3 or 2.4, but the car is much more confortable with 2.0.

What do you think for a use at low speed?

Many thanks

[FROSTYBALLS]

Running tyres at 2.0 bar rather than the recommended 2.3 bar, is actually a 12% under-inflation. Extract from the Kwik-Fit website:

Under inflated tyres will have uneven contact with the road and will exhibit excessive wear on the inside and outside edges of the tread if they are left underinflated for some time. Not only does low tyre pressure wear your tyres out more quickly but you may also experience increased rolling resistance with the road which means reduced fuel efficiency and increased CO2 emissions.

[craggle]

I think the reason they say so high is for economy.

I used to run mine at 30psi all round (2.0 - 2.1 bar) and the tyres wore perfectly evenly and it was a bit softer on the road. Downside is increased fuel economy.

I now have 205/45 17 tyres for the summer and as they are wider you can run them even lower, 28-30psi and they are great.

If you think that is low I have an AC Cobra look a like car I built a few years ago and that has much wider tyres and as the car is pretty light they need only 20psi in them. There is a way of working out the ideal pressure based on weight of the car, tyre size, load rating etc.

Craig.

[Guest]

I stick with the book pressures and have found the tyre wear to be very even, (Tyres have been on and off, winter-summer, so swapped around front to back for more even wear too), especially on the winter Yokohama tyres recently removed -due to legality. Getting some more before the month end all being well.

Got the new tyres fitted, very happy.

Edited December 6, 2015 by Guest

[Cyker]

It's really horses for courses. In my Yaris, at 30 PSI, I get high shoulder wear, but find that increasing it up to 38PSI at the front made the wear much more even (And increased fuel economy to boot!). Beyond that didn't really give any more benefits and started to affect cornering grip.