My Aerox is having trouble starting?

Hi there, I'm having a few problems with my Aerox and wondered if you could help. during these cold months it has been struggling to start. so i checked out all the automatic choke and the thermometer sensor in the head to check they were working. Didn't seem like they were so i changed both of these parts. Its working like it should now with the pin in the automatic choke when cold moving down to let more petrol through. Starts up fine until you take it out and then come back and go to start it again in the morning and it wont start. But when you finally start it its fine and then if you were to leave it a couple of days it will start up fine. It just seems to be when you take it a little way. What could you advise would be the problem. Thanks