I could use some help figuring out the source of this issue and a solution. This is a 71 CB350 I was attempting to start. Almost immediately after hitting the starter button the knocking sound can be heard and you can see how the cam stutters and stops. I recently adjusted the clutch cable, cam chain, valve clearance, and points and to the best of my knowledge everything was done correctly and to spec. It was also making this sound before the adjustments. There isn't any knocking when using the kickstart, or turning the rotor.