Query approved

@Rajhkumar - Please post your intro in 'Who are you' section.
Coming back to your issue. I would think you'll need to work on the carb for the mileage factor. The Air Fuel Ratio (AFR) screw on the carb needs some tweaking. Take the bike to some good mech and ask him to tune it.
Decent stock bike should be giving anything around 35-40kmpl. However, considering other parameters, if I were you would be happy if returns around 30-35kmpl
Also, there are other factors affecting the mileage would be poor quality of fuel, air leaks, dirt etc. First lets see how the bike responds to the tuning and will take it forward from there.

Question:- Did you say RXG 1995?? Check the RC book again.