I have a standard GS, but here's what works well for me:
Front: 2.4 to 2.5 Bar
Rear: 2.9 Bar
I don't what those pressures are in your earth money, but I am sure that google's convert: keyword can help you.
A tip I got off the GS mailing list: check pressures when STONE COLD, i.e. before riding. Ride some (i.e. enough that your tyres are definitely warm, at least 20 mins), then leap off and check the pressures again. The pressures should be 10-15% higher. If they are less than 10% higher, your pressures were too high to start with, so let out a little bit of air. If the pressures are more than 15% higher, then the pressures were too low, and you need to add a bit of air.