Do not stuff around with oil in an Opti...proper Optimax DFI oil or as Huey suggests XD100 can be used (he loves his XD-100).
Alby
Running a decent oil like XD50 in your carb Yammy only makes life better...less smell, emissions, better lubrication stability etc.
PM to Huey will sought you out with some XD50.
C.