fzs 600 carburettors

[His Dudeness]

Yep all clear. But surely that wouldn't explain why it will run for 2 seconds when it's been left for half hour then not run at all? It's baffling me. I think the carbs are gonna have to come back out

If that's the case then there's a restriction somewhere and the carbs aren't filling quick enough. Try hooking up another fuel supply straight to the carbs and see if it runs