I think Richard has got it right, I bought a 2010 Speedmaster late last year and had a bit of a problem with the bike stalling at times when I went to take off after I was stopped somewhere usally at a set traffic lights not very good at all.
So I took the advice I have read here and on another site turned up the idle speed and gave the bike more revs when I take off and so far so good, but in saying this I have stalled it a couple times and I know it is my fault just not giving the bike enough revs, because I have came off Harleys with there low down torque you don't need to rev as hard and sometimes I just get it wrong but the more I ride my Speedy the better it will get cheers.
