Is it possible that the master link on a chain tightens as heat builds up? I still have a weird vibration on my k6. Chain tension is fine, no tightspots as well when I checked it when cold . BUT,,, once the bike’s been driven a short while the vibration starts at high speed… I have a feeling that the masterlink is too tight … especially when warmed. It looks like from above that the chain has a slight wobble upwards and downwards in it when I feel the vibration at speed. I hope by replacing the link the vibration is sorted…!!!!