I've tended to run around 30ish psi f+r on both my 250 and 400 on the road and track with no problems ever since they were lowered to that when I did the California Superbike School (level one) and forgot to pump them back up afterwards.

Most people seem to be of the opinion that you lower tyre pressure on the track as the tyre gets so hot that the air inside expands more thus raising it again which probably does occur, but when I did the school the tyre guy there (I believe he was from Dunlop) said the main reason for running them lower was that you could get away with it as it would increase the size of the contact patch and there is no risk of damaging the rim as there tends not to be potholes on the track. So with that in mind in theory on the track you can just keep lowering them untill you either start to go slower or don't like how it feels.

When I checked my pressures at Llandow (1) they were down to 28psi f+r and that was fine.
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