If you are comfortable in riding bike in mountains and have done it before than there is no problem in manali during winters unless the roads gets blocked. Kit up properly and go for it.
Hi Satyabrata if you are ohk to travel in freezing temperatures in the manali hill top then you may go ahead. Driving with bike has its pros and cons. You will be avoiding the traffic and long waiting for the road clearance in mountains however the temperature around -2 degree celsius will be super challenging to drive a bike at that altitude.