Take the baffles out
Start it up and take it for a run
Then when at a stand still hold the throttle on mid way for a couple of secs then blip it up to the limiter or near it and the flames will just start flying
Have a look at this also from a guy Fostersmonster who use to own an XTX
http://www.youtube.com/watch?v=-eEwUXTMwh0