fuel/air mixture?

[Dead Eye]

I have this issue - if I get the bike to start straight away then I have to hold the throttle open a bit until the revs begin to climb. Then I can safely put the choke on. If it doesn't start first time, or it dies then it becomes a bugger to get started. I end up thumbing the starter and rocking the throttle open and closed slightly until it catches and starts up. I've kind of gotten used to it and this is only the case when the bike is cold

I don't think I have a fuel mixture issue though, as it was definitely over-fuelling before and after its been adjusted the problem still exists