Wednesday I will get by post the gap tools from ebay and I will adjust the spark plugs to 0.7mm . I will let you know if is any change .
The bike run very well except 5000 5400 rpm .
If is the problem from the gap of the plugs , should not be vibrating at all Rpm ?
Here is video with full rpm progress , cold to warm engine .
https://www.youtube.com/watch?v=S5eSHl82qcA
Spark usually fails to jump the intended gap when the engine is doing the most work. As in when the cylinder pressure is at its highest like 6th gear cruising along and hitting a hill. Until the hill is so great that the vacuum drops, the engines internal cylnder pressure is climbing. Events like this create tremendous load for the ignition system and if something is wrong, you may feel it as a vib. Thats not to say the drive train is not a factor as it may be....
So the question remains; did you check the plug gap and did you verify the caps were snug to the wires (cut any material off the wires).
That video makes it sound like it may have a valve on the loose side. Its the ticking sound.