I wonder how hots your engine getting. The cooling system apart. All parts re-act differently. Think about running in etc. It does not make a sound when you clutch it. I wonder if thats where to look. Pressure plates, spacers, plates maybe a worn item in there especially if they are reacting to temp....Still not sure but im only trying to help mate ...... could be well out though, just an idea ?

 

the thermo said 190 when i started to faintly hear it, i usually hear it all the time because traffic will put me at 228 or so when the fan kicks on.
that is running engine ice. last few times i rode it the weather has been cooler same with the roads so it hasent even gotten to 190.
i have the forks off currently so i cant do any more finding out, but it totally does it when it gets hot, i wanted to try with a clutch pulled in and with it out of gear so, in a few days i'll get her out again.