I havnt got the hang of it, yet? My bike is only six-months old and I am having a-lot of bother trying to start it when warm? From cold, no-bother, when hot,no-bother. But if its been left for a half-hour. It-wont start? I can never get the manual-choke right The starter motor whirrs-away. Is there any-way that I can put it onto automatic-choke?...........That is the problem?