Ok, I'd be interested to hear peoples thoughts on this. I have done somewhere between 15 and 20 trackdays and have always dropped my (road) tyre pressures down a few psi - Usually run something like 28-30psi front adn 30-32psi rear. Today I went to a new track and was noticing that my tyres felt good at the beginning of the session but started to slide towards the end. A few guys in the pits said they were running around 34-36 front and rear
which I thought was way to high, so I went and quizzed to the Bridgestone guy who was giving out this advice.
He said that running lower tyre pressures gives a larger footprint on the track. I agreed. However, he then said that the larger footprint doesn't generate enough heat or the heat is to dispersed across the tyre so they don't get up to their correct working temperature. This causes small level cold tearing (the 'large' river like patterns - usually in the spot where you get on the gas). He said if you run the same pressures as on the road - maybe 1-2 psi either way depending on preference. Then the tyres footprint is smaller and the heat generated is much more focused, which is how the tyres are designed to work and offer the optimum grip. He then went on to say that you know that you tyres are getting up to temp because the river like patterns are much much smaller - that is the sweet spot.
I tried this out and for the first few laps, they felt awful. I was sliding all over the place - one corner, I could feel the whole bike drifting sideways as I exited. However, after a few warming laps, they actually felt better than before?
So, what is correct??
(remember this only applies to road tyres - not race tyres)