Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
If the fuel line is blocked or kinked or has a poor flow from a filter then I've found number 4 can go out of play. On my bike it was intermittent and due to a cheapo filter that wasn't allowing enough flow, also it was quite tight to fit a filter in so the pipe was bent at a funny angle and was restricted.