I put 3 oz of seafoam in my 650 crankcase last fall, about 2 weeks before I did a full oil and filter change.
The instructions on the can says you can use it in your oil and gas. I dont know if I would want to put it in with fresh oil.
I doubt it would hurt anything - could not find any negative reports on using it in the oil on a MC with google.
The thing you need to worry about on a MC wet clutch is putting something in that is too slippery, like a silicon oil additive.
BTW, I like the way autospell changed your title on this thread: seafood LOL!