Help lexmoto street 125 cutting out

Hi guys, need some advice , I've got a lexmoto street 125 bike, it had been sitting for 3 months so the battery had died . I've now charged the battery and it fired up fine. However , when I give it some throttle it cuts out . The furthest I've got with it is about 5 metres in first then it just cuts out. Any ideas on what might be the problem?

Thanks in advance . John

 

Drain the tank and use fresh fuel for a start. Clean the plug. Clean the air filter.

 

Thank you , il give it a go tonight