OK guys not sure if anyone on here has any idea but i may aswell ask before taking it to the bike shop.

My son has an old 50cc crosser, and after riding it for about ten minutes it just stops running, if you try and start it, it will start but then stop before you can rev it almost as if there is no petrol. There is petrol getting through and i have stripped and cleaned the carbs, ive renewed the spark plug and check all the head gaskets and tightened everything up.

Im now starting to wonder if it could be an electrical thing that rears its head as it get hot??...never any good with points and coils etc so anyone know if one of these could cause this?? or any other ideas...

Thanks alot its driving me mad...:)