I think this is a normal deal...but i was listening with my head next to the crank case today... and i heard a lot of whining comin out. I'm new to short stroked high performance 4 strokes. I've only had the bike for about 2 months, and this is the first time I've had my head close enough to hear it. It just sounded like way more engine noise than my 2 stroke put off. But then again my 125 didn't have dual overhead cams, 5 valves, or giant gears on the inside. Like I said it's probably typical and I'm probably being paranoid. Thanks in advance for your replies.