[Resolved]  Bajaj Auto — engine problem of ns200

I had just purchased ns200 and i got an engine problem. First servicing is already done. When its cooled for hours it will give a best sound and pick up too but after 20-30 min of running, some irritating sond come from the engine and the pick up will not be good aswell. I dont know it will be like this in beginning only or what. Its really irritating. My expectation was not this. Whats wrong please give some feedback.