2013 Bonnie SE with approximately 11,500 miles on the clock has developed a rattle somewhere on the right side when the engine is loaded at the higher RPM range (like normal shifting range, not pegging the rev limiter). It sounds like it's coming from the right side cover, but it's hard to peg down since the bike has to be moving. It doesn't appear to be chain or sprocket related, and the only things under the right side cover are the stator, rotor, and CKP sensor. I checked the clearance on the CKP and it's within spec. There is a blank spot on the rotor where a couple of teeth would be, but it doesn't appear that anything has broken off; I'm assuming that's from the factory and used as a synchronizing trigger for the CKP. I don't feel any free play in the rotor or bolt, and the retaining bolts on the CKP, stator, and wire clip are all still tight. The only thing I can see is that It does look like the rotor has been wearing on the stator, but since I can't find anything loose I'm not sure that's actually the case. Any suggestions on what else to check? Since I've got the oil drained anyway would it make sense to go ahead and pull the left side cover and check the clutch? If I already had the gasket I'd just go ahead and do it, but expense + lead time for a new one makes me a little hesitant to do that without good reason.
As Joe has said it does look as if the rotor is wearing on that one part of the stator. Could you rig up a fixed pointer and rotate the rotor to see if it is running true or not?
Turns out it was in the exhaust system. The clamp on the slip-on had worked loose, loose enough that I could move it by hand. I was due to change the oil and check the valve clearances anyway, so no big loss in pulling the side cover.
Making the gasket is not crazy hard. Xf-acto knife loosleaf paper hole punch Sheet of gasket material from auto parts store.