Hi Neil, I always drain my carbs if I store the bike for a month or more. Ive just dragged my sport out of deep sleep from 4 1/2 years and it started first time on the old fuel once carbs filled, although I use high octane premium stuff as it pays off in storage and rewards by being a smoother ride.
There is a knack in starting and its > choke on, spin it over the once only, rest it for 3 seconds then hit the starter again and mine then starts and I can turn choke down just enough to keep the revs above idle.
Hope this helps Eric