This is for a 919 but since most Hondas from this era have CCT's go out I thought I'd give it a shot. The only thing that worries me is the rattle is the worst on left side and the CCT is on the right.

 

could be a warn cam chain which means its loose and rattling around. im under the impression that CCT's dont "go out" slowly, but fail with a bang. but it could also be 50 other things. regardless id get it checked out before you ride it or even start it again. you dont want to do damage that can be prevented if u dont start it.

 

+1 jscobey

Get it looked at!

 

It sounds more like grinding gears, I hope for you that its only the starter clutch gear wich doesnt retract and grinds on the starter gear

 

The sound goes away above 3K, it just purrs The noise is only at idle and below 3K.

 

why risk anything? have it looked at before it grenades. or nothing could happen and you could be fine. ill tell you for sure tho that engines shouldnt make any weird noises like that so whatever it is its not good. it might not be all that bad either, but its not suppose to be doing that