I own a pulsar 150 UG4 2010 model since april 2010.\r\nSince then i notice that my bike gets over heated even?

I own a pulsar 150 UG4 2010 model since april 2010.\r\nSince then i notice that my bike gets over heated even in short trips say less than 15-20kms at a constant speed of 60-65km/hr. and burning smell comes from my bike once stopped. I change my engine oil every 2500km. My bike gets so overheated that i am unable to keep my leg in the brake pedal. I have tried changing all the best available engine oils for my bike from SHELL to CASTROL but the problem still remains. Due to this overheating problem in my bike i refrain from going on any long trips on my bike. Please suggest me a feasible solution asap.