Busa low idle on start up?

[bbluesilver]

Hi, When i fire the bike up first thing in the morning or when I am leaving work, the motor fires up as normal but them after a second or two it will die down to almost stalling.
I sounds like the choke isn't coming on or it is loading up.
Then a few more seconds later the revs come back up again like normal as if the choke has kicked in.

Dose anyone know what is happening here or has it happened to anyone else?
The bike has only done 2,200 km and the only thing done to it is the computer flashed and Yoshi pipes .

Any information is appreciated.
Cheers.