LOL, Very true that he may think that he knows more than he actually does!

In regards to the cutting out, yes the engine completely dies and needs to be restarted. This has only happened to me twice, and it was after I put in a tank of 91 RON fuel, since I have been using 95/98 RON I have not had the issue.

I am surprised that my mate had the cutting out issue, and I have no explanation as to it did it to him. Maybe he was giving it a red hot go and is not used to the bike or something?

The is a Kev's mod that has been fitted, but I must say I have not played with the setting, as it was set up by the previous owner and I am not sure what he has got it set to?
The only information that I have is a note on the bikes manual that says "Kev's Mod @24 > adjusted to 19"

I live in Melbourne would you suggest that I take the bike to get it checked out at all?

I love riding the XTX and it does feel good to me, so I guess that is what counts!