Why Do Hindus Wear the Tuft of Hair Called Shikha
http://goo.gl/izo8ag
It is an established rule that anyone who recites Vedic mantras should not have hair on face and head. So, those who need to perform Vedic rituals are advised to remove their hair.
The shika covers that part of the skull wherein lies the final chakra – the Shasrara Chakra. He retains the hair to protect it. Then the question would arise, why shave of the rest of his head?
One of the main rituals of the brahmin’s practice is the Surya Vandana, and Sandya Vandana. It is believed that the sun is the primary source of clean energy not just to the physique, but also to the mind. He wants the uninterrupted rays of the sun to fall on his brain and soak in. (Remember, hair, like our nails, is dead matter.) He stands in the sun three times a day to pray, chant his mantras and meditate – facing the sun.
Significance of Shaving head – It is a symbol of renunciation. If you see materialists, they are extremely fond of hair. Decorating hair etc pulls us into bodily consciousness. This is not good for practicing spiritualists. So as an indication of renunciation from material consciousness devotees shave head.