Cam chain buzzing noise

[darrsi]

Does it happen in at tickover or reving the engine in neutral or when the clutch is pulled in?

Noise starts when the bike is warmed up.
If I pull the clutch in when moving the noise subsides, but if I rev the engine when rolling with the clutch in it "vibrates".


But then I found (when warmed up) I can put the bike on the stand and raise the revs to about 3000rpm and recreate the noise. On tickover without revs you can't hear it.


For that reason I thought it may be a fracture impeller in the water pump, but when I went to my mates house he got a screwdriver out and 'listened' to different parts of the engine and the main noise definitely came from when he had the screwdriver on the cam chain tensioner.