Winterizing on the coast is different than in the interior, going from a two stroke to a four stroke adds a few additional items as noted previously. A few thing that I did that have not as yet been mentioned ( on my old Enduro). Fuel Stabilizer: On the last few tanks (portable) I added some Seafoam and some marine fuel stabilizer. I transferred the unused fuel to a Jerry can(s) and stored it inside a cupboard in the garage. I purged the fuel lines including the ones to the carburetors ( removed drain plugs first) with low pressure compressed air and drained the filters (replaced every two years). Because I live on the coast where last year the coldest it got was -10C , I removed the thermostat ( an easy job on the Enduro) and used an RV/marine propylene glycol antifreeze good for around -40C for the cooling system. I should say that if after removing the thermostat I noticed any buildup of salt crystals, I would use Salt Away first. Fogging and leg oil change were next. Before storing a good spray with WD-40 inside and out finished the job.
With the four stroke the only difference I can see is replacing the engine oil and filter. Don't know what to do about the fuel injection system system, hopefully the fuel stabilizer will be enough.