Tyre pressures for the road

[reAnimate]

Got back from doing a track day at Mallory last weekend.
Recommended track pressures were starting off at around 31 / 31 aiming for 36/36 when hot.
Any reason why I shouldn't be aiming for the same presures for the road?

Seems odd that the recommended presures for my cbr 600 rr are 36 / 42

[slim_boy_fat]

You spend more time on the centre when on the road. Thats when you over heat a tyre more. Reason to lower them when on the track is because you should be on the side more often and get a bit more grip. Also stability on the road will be affected, and you can never keep as much heat in the tyres when on the road as you can on the track.

I'm surprised they suggested pressures quite that low, i would have thought 33/34 cold 38 hot

[biker's nemesis]

On the track I run mine at 28psi rear - 29psi front and on the road 39psi rear - 39psi front.

[reAnimate]

Hot or cold, surely tyres are designed to perform at their optimum at a particular PSI?

[m3psm]

Not sure how it works on bikes, but on cars it's about the temperature, not pressure. You adjust the pressures to get an even temperature accross the tread of the tyre.
If the middle is hottest it's over inflated and if the sides are hottest it needs more air.
I know some bike tyres have softer compounds towards the edges of the tyre, so not sure how these principles work, but assume you'd still want even temperatures accross the tyre.

[shot2bits]

I run 36 / 34 on the road, 34 / 32 on the track... Appears to work well for me, tyres are Diablo Corsa III's.

[slim_boy_fat]

Yes but remmber your ideal gas law, pressure tempreture and volume are all linked.

Tyres are ment to havve correct pressure when working hard and hot. On trake tyres work hard and stay hot adn keep there pressure up.

On the road tyres are not worked are hard and run much cooler hence requiring more pressure.

Tyres will work across a range of pressures obviously if you go outside that you will get into trouble with stability or grip/ride comfort.