Anyone help? I'm not too good with engines....

I've noticed that when my CBR1000F-L is idling, every 30 or 40 seconds there's a kind of splutter from the right can. Can anyone explain what it might be?

Background info:
13,000 miles on the clock; she always starts first time, with choke when cold; idle speed when warm is 1,000 but goes up and down a little; she wasn't used from Sep 05 to Jul 06; I checked petrol consumption on a recent motorway run and got 41 mpg at an average 80mph and she ran 'sweet as a nut'.

She's gonna be serviced and dyno tested in a couple of weeks, I hope this will uncover any gremlins, but in the meantime if anyone has any ideas, I'd appreciate it.

Thanks all.

BTW, great forum!