Hopefully its not been left for that length of time with old corrosive oil in it. I'd crank the motor over a few times before firing it up to get rid of the oil in the bores, don't know if it would contaminate the Lambda sensor or not
Other things I'd do is check the condition of the oil pump drive pinion (remove the pump and take a peek up the hole; check you've got the latest primary chain adjuster fitted (if you haven't, it'll already be broken and could send chunks into your gearbox and wreck it). It'll be a good opportunity to fit the latest, leak free, gasket
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If the bike has been resting on its sidestand then the needle roller bearing behind the front sprocket will be dry, so poke a hole in the centre of the rubber seal on the exposed end of the mainshaft, and inject a little oil into there. Seal it up again with a smear of silicone. For a few quid you could prize the cover off, lube it good 'n proper and fit a new cover.
When you get time, drill a 3 mm hole in between the fork on the swinging arm where the rear shock eye fits. It acts as a water drain and you don't then lube your bearings with water
A tie wrap around the top of the rubber boot on your clutch cable will also stop water entering the cable and then travelling down into your primary.