Hi guys I've just bought a 2006 Rx8 6 speed 231bhp version and im curious about pre mixing. I'm in the UK so what oil can/should i use to pre mix?

 

Have a read through RX8help.com. It's written by a member here and condenses most of the questions like this.
On premix in particular Premix

Long story short: any oil that has JASO FC or FD rating. Typically this is high-end bike or snowmobile oil, not the chainsaw or watercraft stuff.

 

The Protek-R stuff from Pettit Racing is not bad either. You can find some easily in the UK.