@ Shahabkb
Bro i dont thinks the matter is like this...!
One of my Friends who didnt new anything about bikes purchased a cd70 and without running started speeding it upto 80Km/Hr.
But soon some of his friends saw him speeding his new bike and explained him running process....
I dont think that this prob. is due 2 under running engine...! It cant be! not logical!!
Aisi koi baat nae k new engine Hard ya soft hota hai... Engine Hard & Rough tou hota hai but even then bike bhagti hai.
I dont knw about carburator adjustment of speed 4 bike safety as mentioned by someone in previous posts... Maybe woi hua ho apki bike k sath..?
But even then bike ko shoor bilkul nae krna chahye.. INfact new bikes ki sound tou bohat he kam hoti hai!!
I advise u 2 get ur bike checkd from where u bought it and ask them if they did any carburator adjustments or nt?? Call them B4 u go..
Its a question of ur 65Ks investment not a non serious matter!?
Best of luck!