lexmoto problems

Hi All
I've just joined this site as my son has a lexmoto tornado 50cc and is having starting problems,
It will start and run for about a minute then just cut out,
it has had a new head gasket set put on it and the carb taken off and given a good clean
Any advice on what to try next would be grateful, Clare

Is this just a problem with it idling or will it cut out while riding? If it's just an idlling problem then prehaps the idle mixture and/or idle speed screws on your carb need adjusting. Failing that you could just replace the whole carb as they are usually cheap to replace.