Hi all: Jim has kindly offered to post an amateur video of an odd new noise that my 1976 C-model began making last night after a spirited ride. She starts and runs fine - but there is a rapping / knocking sound that I’m sure wasn’t there before. This morning I adjusted the timing chain and the valves (the RH exhaust was a bit loose - but not excessively). I then did a head re-torque, which went fine. ....but, the noise is still there. Any thoughts - or is it just my imagination?