Hello First of all wearing helmet does not cause hair fall. I would recommend you to continue wearing helmet while driving for your safety. Sudden hair fall in large quantity can occur due to some illness in recent past, physical or mental stress, thyroid disorders, nutritional deficiency or certain medicines. Please visit a qualified dermatologist for diagnosis of underlying cause and then take treatment accordingly. Do not fall pray to advertisements as single oil can not be solution for all types of hair fall. Hope this helps you.