Engine noise I have a 450 Xc . I got it a few months ago

And it is brand new only 75 miles on it when i got it. At the 600 mile mark i did the valve adjustment and changed the oil, after another 100-150 miles, the normal ticking that you get from the motor started getting louder. I checked the adjustment on the valves again, they were good to go, and after another 50 miles or so i changed the oil again to make sure there were no metal flakes in the oil, which there werent. Do the 250's just get a little noisier as tehy break in? It seems to me its coming from the bottom end. It has automatic cam chain tensioners, so i dont think its that, and i have checked to make sure everything is tight like it should be. The ticking does go along with engine speed, and at 55-60 mph you can just barely hear it over the wind and road noise. I have worked on cars for several years, and i know some engines are just normally loud or ticky, but this is my first bike that i have ever really messed with. This normal for this bike? ,i had a 82 yamaha 650 and with 40,000 miles it was the quitest bike i ever had. i realize that doesnt really compare to ur bike but i wouldnt expect an engine to be louder after that few a miles. i would really suggest finding a forum especially for your bike (theres bound to be one) and asking around, its really a bike to bike difference ,,,