Does anyone have a video of their 08 rmz they can link to see if mine sounds ok? Since ive bought it its made a knocking noise that a same year 250 does not make. Last time i had it apart i needed to adjust the valve clearances slightly but i still had the same noise. Cam chain is fine also. When i got the bike the guy i bought it off assured me it was a new piston but u never know. I was thinking the sound was possible piston slap or do the engines give off a knock anyways? thx forgot to mention, filters always come out clean with no shavings.