TWs have a combined sump, which means that the engine, trans, and clutch all run in the same puddle of oil. That is why it is critical that you use only oils specifically blended for motorcycles. Maybe other oils will work, maybe other oils will waste your clutch and allow your cam and followers to self-destruct. Maybe not. Is it worth the risk considering the $2 difference in price.
If it was my bike, I'd change the oil to a dino blended for motorcycles with wet clutches with a viscosity of 10W-40. Valvoline and BelRay make good choices. Then I'd shift it to 5th, adjust all the play oput of the clutch to open relieve as much pressure on the plates as possible, pull in the clutch, and push it around for a few minutes, forward and backward. Then I'd lube every point in the manual, check the valves, spark pklug gap, cam chain tension, and every adjustment on the bike. Next, I'd pull the battery, fill with distilled water, and charge with the lowest output charger I could find. Then I'd go over the bike top-to-bottom, end-to-end, and check fit and cleanliness of over hose, wire, and piece of hardware. Next, pull the tank, wash it out with kerosene, drain, install a new petcock (not much more expensive than rebuild parts) and fill with fresh gas, preferably without ethanol. Finally, I'd overhaul the carb, install a #130 main jet, stick a small flat washer under the needle circlip, and set the pilot screw about 2.25 turns out.
Then I'd ride the piss out of it.
But that's just me. You can half-assed your prep and ride a half-assed running bike if you want.
