My last tread has seem to been deleted. But I have a honda Forman 450es with a strange rattle which seems to be coming from the head and only on the down stroke of the engine when idling down on the throttle. I have replaced cam chain and tensioner the guides were in good shape so didn’t need to change them hav also re seated a new exhaust valve and re steated my inlet valve which were like brand new. Valves are set to 0.006 and can’t seem to figure out why this noise is in the head it seems to be!? Would appreciate your help on suggestions on what could be wrong wit the head??