I dont know how you are calculating your average, because even in its stock condition, the mileage isn't THAT bad. The mileage you mentioned can be of a Deluxe (which has the worst mileage in CG-125 category)
Heres how to check the practical fuel mileage of your bike.
There is a capacity of 9.2 Liters in it. 2 Liters out of 9.2 is RESERVE. That gives us 7.2 Liters Remaining.
Now, get the Tank FULL. Note the meter reading. Lets say its 20,000 KMs on ODO meters. Drive around like usual, And when the bike enters RESERVE fuel mode ... note the meter reading. Lets say the ending reading is 20,330KMs.
Calculation:
20,330 - 20,000 = 330KMs (This means you drove 330KMs on a FULL Tank)
Divide the 330KMs to the Capacity of 7.2 Liters (which is excluding reserve)
330KMs / 7.2Liters = This gives you 45.8KM per Liter.
Another thing, Brand new bikes have their mixture VERY rich. I have taken a lot of peoples' opinion on this one and they say its for the running of the engine. Dont touch the Carb before ATLEAST 5000 Kilometers. After that, you can get it Re-Adjusted for FAIR mixture (not too much, not too less ... just the perfect combination).
The problem here is ... not many people can do it WELL.
Anyway, i hope you get the message
Its understandable. Seen A LOT of examples of 50+ mileage so yeah, i believe you on this. BUT ... that can ONLY happen if you drive is below 60KM/h speeds AND you have your carb adjusted.