Hi, my friend just bought a 2002 yz 426f with a fresh rebuild, I just want some other opinions whether the sound radiating from the cams or cam chain. i cam to the conclusion that it might be just the nature of the beast or that the cam chain is loose. i mean its a constant sound, it gets louder with the rpms. I havent delt with this model before. i just want some info on this bike and whether or not it could be the rebuild or just normal engine noise. Thanks for your time!